


Alpha Spunk

by Destielshipper4Cas



Series: Alpha Spunk & Omega Slick [1]
Category: Supernatural
Genre: Alpha Dean, Alpha/Beta/Omega Dynamics, Alpha/Omega, Barebacking, Bottom Cas/Top Dean, Bottom Castiel, Coming Untouched, First Time, From Sex to Love, Frottage, Heat Sex, Knotting, M/M, Marathon Sex, Marking, Mating, Mating Bond, Mating Cycles/In Heat, Miscommunication, Mutual Pining, Omega Castiel, Omega Verse, Plot What Plot/Porn Without Plot, Rut Sex, Scenting, Smut, Top Dean
Language: English
Status: Completed
Published: 2019-07-06
Updated: 2020-03-05
Packaged: 2020-06-22 10:11:23
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 16
Words: 24,764
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19665319
Author URL: https://archiveofourown.org/users/Destielshipper4Cas/pseuds/Destielshipper4Cas
Summary: In order to alleviate bad heat cramps, Cas’ doctor recommends ‘potent alpha seed.’ At the drugstore, he not only gets his prescription filled, but meets the sexiest alpha alive…





	1. Chapter 1

“Wow. That is one kinky doctor,” Gabriel commented, a huge grin splitting his face.

Cas scowled at him. “She’s not kinky. Apparently, it’s perfectly normal for omegas with bad heat cramps. See?”

He showed his annoying brother the prescription for ‘one bottle of potent alpha seed, potency level 3.’ Gabriel promptly took the prescription to take a closer look.

“Why do you want me to go get it for you then?” Gabriel asked, one of his brows raised in amusement.

“You’re an alpha,” Cas explained.

He could just imagine the looks he would get if him, an omega, bought potent alpha seed. If enduring his brother’s teasing got him relief from the awful heat cramps he’d been suffering these last couple of heats, then he would have to grit his teeth and let him get it out of his system.

“Exactly. I don’t need ‘alpha seed.’ The pharmacist will think I’m sterile and can’t satisfy my omega.”

“Since when do you care what other people think of you?” Cas challenged.

That seemed to give Gabriel pause. “True,” he acknowledged and Cas already thought he had won, but then Gabriel went on, his grin spreading even wider, “But I also don’t want to give up an opportunity to see you squirm.”

“You’re an assbutt,” Cas said, ripping the prescription out of his hands and storming away.

No way would he go to his usual pharmacy. He would just have to go to a place far enough away that no one recognized him.

* * *

Cas had walked by the drugstore three times without going inside when he finally got up the nerve and pushed open the door.

There was an old lady somewhere off to the side, looking through the shelves, but apart from that, the place was empty. He had been right to wait until most people were probably having lunch.

Glancing at the old woman’s back, he quickly made his way to the counter. The sooner he got out of here, the better.

The alpha behind the counter was sitting in a chair and got up when he saw Cas approach. (Was that a ‘Busty Omega Beauties’ magazine he had just put away? Surely not…)

He was wearing a plaid shirt and jeans and altogether did not seem very professional.

“Uhm… hello?” Cas said, unsure if this alpha was the pharmacy tech.

“Hi,” the alpha greeted back, flashing him a huge smile that made the corners of his beautiful green eyes crinkle. “What can I get ya?”

“Uhm…” Cas said again, his fingers searching for the prescription in his coat pocket.

He cast a quick glance over his shoulder at the old lady who had her back turned to them.

“I need…” Cas lowered his voice and then trailed off altogether and simply slipped the prescription across the counter.

“Ah. Potent alpha seed.”

The alpha nodded understandingly as Cas looked over his shoulder again. Fortunately, the old woman didn’t seem to be able to hear all that well as she continued perusing the shelves.

“For my brother,” Cas quickly mumbled, ready to throw Gabe under the bus.

But the alpha only smiled knowingly. Then he looked back down at the prescription.

“Rare to come by these days, huh?” he asked, looking up and winking at Cas.

Was he teasing him? They were complete strangers, why would he be teasing him?

Cas knew he should have asked Balthazar. His ex would have teased him, too—and probably suggested a round of hot heat sex to cure him—but everything was better than turning beet red under the knowing gaze of the most gorgeous alpha he had ever laid eyes on.

“Don’t scare away the customers, Dean.”

Another alpha walked out of the back room and joined them. He was even bigger than ‘Dean’ and he, at least, looked like a pharmacy tech complete with white lab coat and nametag that read ‘Sam Winchester.’

“Really, I leave you alone for five minutes…”

“Let’s get real here. That was at least seven minutes.”

Dean raised his eyebrows at Cas as if he expected him to confirm that claim.

When he did no such thing, Dean added, “You should start paying me.”

Sam rolled his eyes and then looked at the prescription, which made Cas blush once again.

He turned to the shelves behind him, snatched a small bottle that luckily was not transparent, and put it on the counter. Then he grabbed a syringe and put it next to the bottle.

“You have to insert 10 ml into the rectum,” Sam began explaining.

“Do you mind?” Cas interrupted, turning towards Dean.

“Not at all,” Dean replied, grinning at him.

Sam sighed. “Dean,” he said, a warning tone to his voice.

The two alphas seemed to have a silent conversation, staring each other down before Dean shrugged his shoulders and sauntered off, leaving through the door to the back room.

Cas wondered if they were one of those rare alpha-alpha pairs.

“Use it once on the first day of your heat. If the cramps don’t go away, you can use it another time on the second day and once more on the third day. No more than three days in a row, though. Not unless you want to experience alpha rejection.”

“Alpha rejection?” Cas repeated, so surprised that he couldn’t help himself. Wasn’t that something that only happened when you formed a bond with an alpha, like when you scent bonded with them and they didn’t want you back?

“’cause you get the sperm in your ass part of the sex without the cuddling part?” Sam tried to explain.

Cas wondered how he could talk about that without blushing. Perks of the job, he assumed.

Sam shrugged. “Some omegas have complained about it, so I’m obligated to inform you that it isn’t safe to take it on more than three days of your heat. The heat after that, you can use it again, though.”

If he needed to use it on more than one day, there probably wouldn’t be enough left for his next heat. But before he could ask for a bigger bottle, the old lady made her way towards the counter, having found what she had been looking for.

Cas quickly grabbed the bottle and the syringe. He would make sure never to come back to this place…


	2. Chapter 2

Thanks to the ‘medicine,’ Cas’ next heat went by without any pain whatsoever and true to his resolution, he bought another bottle of alpha seed at a different pharmacy.

Only this time, the heat cramps were worse than ever, even after taking the alpha seed the third day in a row. He should have gone with what he knew worked best.

Once Cas had finally survived the heat—no thanks to the alpha seed he had acquired—he called the pharmacy to order more of the product he knew took care of the cramps.

Luckily, he hadn’t thrown the empty bottle away yet and so he read out the number on the back.

“The Alpha number is 001241979/69.”

 _“Oh, I’m sorry. We don’t sell that product here. But I can look up where you can get it,”_ the woman on the phone said.

Cas heard some typing in the background and then the woman said, _“You could try your luck at the pharmacy at the corner of 8 th Street and Maple Avenue.”_

Just his luck. The pharmacy he had sworn he wouldn’t set foot in again. On the other hand, it _had_ been a few months and those two alphas probably got so many customers that they had forgotten all about the embarrassing encounter. They probably had embarrassing situations like that all the time.

That’s how Cas found himself back where it all had started.

The big alpha, Sam, was at the counter and when he looked up and saw Cas, he smiled and ruined Cas’ illusion by saying, “You haven’t been here in a while. Can I assume that the last heat didn’t give you any trouble?”

“It did, actually,” Cas said. “Which is why I’m here. I would like a bottle of the same… product of the same alpha as last time. Here’s the alpha number.”

He put the empty bottle on the counter and looked around surreptitiously. There was no trace of the beautiful alpha, which strangely made Cas feel relief and disappointment at the same time.

“Oh,” Sam said, which was not the reaction Cas had expected or hoped for. “Actually, that alpha is not one of our usual alphas who provide us with the product. It was just the one bottle. There might have been a lost bet involved…”

A bet? What kind of an alpha bet his sperm?—That was just his luck. The one thing that could help him with his heat cramps!

Sam seemed to have read his expression correctly as he quickly added, “But I might be able to get more. If you leave me your phone number, I can get back to you.”

* * *

When Dean entered the drugstore that was pretty much empty at this time of day, he immediately smelled it. The sweetest scent that had driven him insane these past few weeks as he had been waiting to smell it again, meet the owner of the scent again.

Before he could ask Sam about it, his brother already spoke up. “Yes, the omega was here, no, he didn’t ask about you.—Not directly at least,” he added in a mumble.

Of course, the omega—Castiel, as the name on the prescription had said—wouldn’t have a reason to ask about him. He had been utterly immune to Dean’s attempts at flirting (and Dean was a damn pro at flirting if his track record of bedding omegas was anything to go by).

Dean himself had worn scent blockers, so there was no way of knowing if Castiel liked his scent or was repulsed by it. Damn regulations. Always had to wear scent blockers behind the pharmacy counter…

“Earth to Dean?”

Shaking his head to get rid of the thoughts of bright blue eyes, Dean looked up. “Huh?”

“I asked if you could provide another sample.”

“Sample of what?”

Sam shot him a meaningful look and Dean’s brain caught up with what they were talking about.

“Oh, hell no! That was not part of the deal. I honored the bet, but that was it. It was a one-time thing!”

It had been weird enough the first time. Especially since one of the possible side effects for the omegas was pregnancy if the birth control failed. Dean did not want to risk some omega out there carrying his pup without him ever even knowing.

Sam sighed dramatically. “Such a shame.”

Even though his words sounded like he was giving up, his tone of voice told a different story.

“I told your omega that I could convince the alpha, but if you don’t want to, I guess I’ll have to search for a better alpha…”

“You should have let me finish,” Dean quickly interrupted him, ignoring the ‘your omega’ comment. Sam had teased him enough about Dean moping about these past few weeks. “What I was going to say was, you know me. Always happy to jerk off into a cup for omegas in need.”

The victorious smirk on Sam’s face should have been unnerving, but Dean was on a mission and so he just snatched the cup Sam was holding out for him out of his hand. Then he rummaged around under the counter until he found his latest issue of _Busty Omega Beauties_ and went into the ‘masturbation room’ as he liked to call it, which luckily was the cleanest in the whole store since it was scrubbed clean every time an alpha used it.

Dean quickly realized that _Busty Omega Beauties_ wasn’t enough. It wasn’t _female_ omegas he thought about at all, but a certain rather flat-chested omega. So Dean put the magazine away and inhaled deeply, pretending he could still smell that delicious scent.

Something about this omega… Just the thought that the sexy omega had used _Dean’s_ sperm during his last heat got Dean going. _His_ sperm had been up Cas’ ass.

What he would give to be the one to pin him down and shoot his load deep inside his ass. Knot him good to make sure it stayed inside Cas where it belonged.

Dean groaned and palmed his erection. Cas would use his seed during his next heat again, coating his insides, marking him as Dean’s.

Thinking about Cas’ sweet honey scent was driving him to fist his cock faster.

He wouldn’t mind knocking Cas up. His belly would be swelling with Dean’s pups. Oh yeah, he’d breed him good, pumping his fertile seed deep into the little omega’s tight ass, flooding his womb with his sperm and inflating his belly, then knotting him to give his sperm the best chance of fertilizing his omega.

He’d flood his ass so many times that he’d carry a whole litter. And just as Cas would be about to come on his cock, he’d sink his teeth deep into his mating gland.

He sped up some more and then—

“Ahhh!” Dean cried out as his cum sprayed out of his cock in thick ropey jets, and Dean remembered just in time to aim for the cup and catch most of it.

As he came down from the high and tried to catch his breath, he was sitting there, dumbfounded.

Okay, that was new. He never would have thought _he’d_ be the kind of alpha with a breeding kink, much less fantasize about _mating_. He had heard about alphas with a mating kink, but he himself had been so afraid of accidentally mating an omega during heat sex that he had preferred to fuck his omegas outside of heat.

Never had an omega affected him like that before and he had only met the dude once. But he simply couldn’t get the intoxicating smell out of his head. Or the way Cas would look at him in that adorably confused way when he didn’t understand a come-on when Dean hit him with it over the head.

What Dean could do to this innocent omega…

But first, he had to make sure he brought his A game when Cas returned to get the goods.

**Notes for the Chapter:**

> I would love to hear from you in the comment section. And no worries, next chapter Dean and Cas will interact directly again.


	3. Chapter 3

It took a while until Sam could call Cas back to tell him that he could pick up Dean’s seed. Dean had to let himself be tested again, even though he had always used condoms. Still, regulations said they had to wait for the all clear before Sam could sell the sperm to Cas.

Sam had commented on the fact that Dean was hanging around the pharmacy more often these last few days so, to throw him off, Dean told him that he had a bet going with Benny on how long it would take him to get into the pretty omega’s pants.

That was, of course, a lie. But Sam had teased him about his infatuation with the omega after Dean had met him exactly _once._ Dean wasn’t the emotional type who’d gush about his crush’s ocean blue eyes ( _so blue!_ ) and sweet smell ( _oh God, so sweet!_ ) that made him want to envelop said omega in his arms, bury his nose in his neck, and never let go.

When Dean eavesdropped on the phone call between his brother and Cas, he knew he’d hang around until Cas came to pick up the seed. No way would he miss him again.

“I’m gonna wash off the scent blockers,” he informed Sam, since his brother was always bitching about how they had to wear them in the pharmacy.

Sam didn’t even look up when he bagged the seed for Cas to pick up later.

“No, you’re not,” he simply said.

“Oh, come on! Customers don’t need to wear them.”

“Well, then you need to stay on the other side of the counter,” Sam replied, not giving an inch.

Dean shrugged his shoulders. “Sure thing.”

He went into the back room to get rid of the pesky scent blockers. He had been told by many an omega that his scent was alluring, so maybe he could use that to his advantage. On the other hand, there was no sense in trying to pick Cas up if he didn’t like his scent. There were spray-on scents, of course, but Dean wasn’t a big fan of those…

Either Cas liked his natural scent or not, in which case—his loss. (Dean ignored the fact that that thought made him a bit queasy.)

* * *

A few days before his next heat, the call finally came that he could pick up the miraculous cure that would make his heat bearable. Cas sighed in relief. He really didn’t want to go through his heat without the alpha seed.

It wasn’t the perfect solution since having to shoot sperm up his ass while also going insane with the need to be filled was one of the least sexy things he had ever done or ever would do. But then again, anything was better than having to suffer through those heat cramps again.

He had almost asked if they delivered, but for some reason, he decided to suck it up and stop by in person again. (It had nothing to do with hoping to meet a certain green-eyed alpha again, who had dominated his dreams in more ways than one, shut up.)

When he entered the pharmacy, he smelled it immediately—the most delicious smell he had ever smelled. It made him a bit weak in the knees and he closed his eyes and took a deep breath, breathing it in. Then, he realized that the smell was somehow familiar and a second later, his eyes widened as he figured out what the smell reminded him of—the alpha whose alpha seed he had purchased.

While making his way towards the counter, he looked around the drugstore and his eyes immediately found Dean, who was standing in front of the counter, his hip leaning against it. When he saw Cas approach, he smiled brightly.

Cas couldn’t stop himself from turning crimson. He had fantasized about Dean when he had used his sperm—he was the sexiest alpha Cas had ever met after all, and at the time, he had thought he would never see him again. Now, he wondered whether the alpha knew that he had been the one to purchase his sperm.

Oh God. Dean was winking at him again. Why did he keep winking at him? Was this some sort of code? Was he mocking him?

Cas had reached him and tried to bring his lips to move, but no sound came out. Luckily, the alpha didn’t have such problems.

“Hi there, pretty-eyes!”

“Hello, Dean.” His voice sounded raspy.

Oh no, maybe he shouldn’t have revealed that he had remembered his name. Was that creepy? It had been months since he had heard the alpha’s name _once_. It wasn’t even like they had been introduced.

Dean didn’t seem concerned, though. His smile just broadened. “Hey, Casteel.”

“Castiel,” Cas corrected.

Dean held out his hand. “Nice to meet you, Castiel,” he said, this time pronouncing his name correctly.

Cas shook his hand and caught himself just as he was leaning in to breathe in more of Dean’s scent, stopping mid-lean. He was a bit disappointed when Dean let go of his hand.

“Here to pick up the goods, huh?” Dean asked and his voice sounded like he was teasing him.

Cas couldn’t do anything but nod, mostly because he couldn’t think clearly due to the intoxicating smell. Damn his heat that was apparently approaching quicker than he would have liked if his senses were already so attuned to the smell of alphas.

Dean, meanwhile, didn’t seem to mind that Cas wasn’t capable of forming words. He just raised his eyebrows and asked, “So... Your alpha’s seed not ‘potent’ enough?”

“Dean! That is incredibly rude!” Sam said, who had joined them from where he had just sold another omega some medicine or other (Cas would bet it wasn’t anything as precarious as alpha seed).

“I am not currently involved with an alpha,” Cas replied, finally having found his voice again. He had known that Dean had not been fooled by his excuse that the alpha seed had been for his brother, anyway, so he might as well be honest.

The wrinkles on Sam’s forehead smoothed out as he said, “Ah. _That’s_ what that was about. Smooth.”

Cas had no idea what Sam meant by that but Dean apparently did, since his expression turned sour as he glared at Sam. “Shut up, bitch.”

Why would Dean call Sam, another alpha, ‘bitch’? Alphas sometimes called omegas bitches. Did that mean that Dean and Sam were involved? How did people subtly try to pry that piece of information out of someone?

“Are you two mated?”

Dean stopped glaring at Sam and whipped around, looking at Cas with wide-eyed shock.

“Oh, God no! Ew! _No!_ —I mean, not that there’s anything wrong with alpha-on-alpha action, just… he’s my brother. So. Ew.”

Cas tried to suppress a smile when the otherwise smooth alpha started to babble.

Dean’s tone changed then and he continued in a husky voice, “’Sides, I’m interested in omegas.”

And again with the winking. Maybe he had an eye condition.

Sam cleared his throat. “So, Castiel, you didn’t come here to listen to my brother’s pathetic attempt at flirting.”

Flirting? Cas looked around. Who was Dean flirting with? He hadn’t seen Dean talking with anyone else before he had arrived…

Dean, meanwhile, leaned over and flicked Sam’s forehead and—okay, now Cas could see that they were brothers.

Still a bit confused, Cas collected his thoughts and said, “You said you had my order?”

Sam was already getting a small bag and held it out to Cas.

Dean waggled his eyebrows and, lowering his voice, asked, “Need help administering it?”

“Uhm…” Cas could feel himself blush once more. “I know how to… uhm… ‘administer it,’” he said, using air quotes.

While Sam was ringing Cas up, Dean asked, “Did you know that fresh alpha seed is 60% more effective than bottled alpha seed?”

Cas had known that, in fact, but before he could tell Dean as much, Sam butted in, “Since when are you a doctor?”

Dean carelessly shrugged a shoulder. “I did some research.”

“On porn sites?” Sam asked.

Dean glared at him. “Don’t you have somewhere to be?”

“ _I’m_ the one working here.”

Yes, definitely brothers, though the exchange left Cas a bit baffled nonetheless.

* * *

Dean was collected, cool, suave, and his record of chatting up an omega and banging said omega in the back of his car was at under five minutes.

So why had he suddenly developed foot-in-mouth disease?

Not to mention Cas was sending him mixed signals all over the place.

Dean was pretty sure the omega was attracted to him. He seemed to like his scent if the way Cas had unconsciously leaned towards him was anything to go by. Plus, he kept glancing at him bashfully, checking him out.

But then he turned around and turned him down. Maybe Cas simply wasn’t into one-night stands. Or he wasn’t into alphas. Or into men. Or into male alphas. While the thought of Cas with another omega was hot as hell, he couldn’t say that he wouldn’t be disappointed if that’s what Cas was into.

He’d just have to come right out and ask before he let Cas walk out on him again.

“So, what’s your deal?” he asked, faux casual, when Cas was handing Sam the money. “You into omegas, or…?”

Before Cas could answer, Sam groaned and chimed in, “Oh my God! This is too painful to watch.”

He handed Cas the change and then quickly scribbled something down onto a piece of paper, putting that into Cas’ bag as well.

“Call him if you want to have meaningless heat sex with an alpha. I can vouch for him. Not a serial killer, just a huge slut.”

“Hey!”

Suave, cool, and collected were overrated. Dean would so punch his brother in his stupid face later.

Dean was still glaring at Sam, indignant, when Cas said good-bye and left.

Sam had the audacity to shoot him an innocent look. “What? You clearly weren’t being obvious enough.”

“I was flirting my ass off!” Dean countered. “I asked him if he needed help administering the alpha seed. How much clearer can I get apart from bending him over and fucking him right here against the counter?”

Oh yeah, he should have bent him over the counter, buried his nose in Cas’ neck, licked him, tasted him…

“Ugh, Dean!”

Dean shook his head to chase the fantasy away and returned to glowering at his brother.

“I cannot believe you! Now he thinks I’m just some knothead who knots ’em and leaves ’em.”

“So? That’s literally what you do all the time.”

“First of all, for your information, I prefer not to knot omegas, but to pull out before my knot pops.”

“Ew, Dean! Gross!” Sam scrunched up his nose. “I don’t want to know that!”

“And second of all—fair enough but doesn’t mean I want _him_ to think that.”

A disapproving frown appeared on Sam’s face. “Wait, I thought your omegas always know it’s a one-night stand going in.”

“Of course, but…” Dean trailed off, dangerously close to admitting his crush and the fact that he wouldn’t mind if a one-night stand with Castiel turned into a two-night stand. So instead he just said, “Oh, shut up!” and turned around to stalk out of the drugstore.

* * *

Since Sam had made him sound like the sleaziest alpha, Dean wouldn’t have expected Cas to call. So he was very surprised when he saw a number he didn’t recognize call later that evening, and even more surprised to find Cas was on the other end.

 _“It occurred to me…”_ he began, and Dean heard another voice in the background chime in, _“To_ you _?! I’m the one who…”_

Then he heard the sound of a door shut and Cas continued, _“…that what you said earlier was a flirtation.”_

Dean was left speechless for a moment, not sure if Cas was just yanking his chain. When Cas didn’t say anything else, waiting for him to confirm, Dean said, “What, when I asked you if you had an alpha or when I said I’d help you administer my sperm?”

There was a long pause and Dean bit his tongue. He should have shut up. He definitely shouldn’t have let it slip that _he_ was the alpha whose ‘alpha seed’ Cas had purchased.

 _“Both?”_ came the reply after a while, Cas’ voice strangely insecure. As if he still wasn’t sure if Dean had deliberately flirted with him.

So, Dean decided to be upfront and said, “Yeah… those were flirtations.”

‘Propositions’ would probably be a more fitting word, but in order not to put Cas off, he decided to go with the omega’s strange choice of words.

There was another pause and then Cas said, very quickly, _“I start my next heat on the 24 th.”_

Dean, stunned, only got out, “Okay.”

_“Your brother said… I mean, if you’re amenable…”_

“I’m amenable,” Dean said quickly.

That had to be the weirdest sex date Dean had ever set up—mainly because he didn’t normally set up sex dates at all.

He usually just picked up an omega, drove him or her back to their place or to a motel and fucked them there—or in the Impala if they didn’t get there fast enough. There was never any real planning involved apart from going out to a bar and picking up an omega. He was Mr. Spontaneous as far as his sex life was concerned. If he was horny, he got himself some. It was as easy as that.

As he wrote down Cas’ address and even the time of day, he couldn’t help the big smile that spread across his face, though.

He simply couldn’t wait for Cas’ heat to start.


	4. Chapter 4

As much experience as Dean had with sexing up omegas, he was kind of a virgin when it came to heat sex. Although he assumed it was much like rut sex, which he had had on multiple occasions.

Still, in preparation for their heat sex date, Dean watched a lot of heat porn, which, unfortunately, didn’t really get him anywhere. The alphas just kept calling the omegas they were fucking ‘bitch’ and grunted things like “Hole made for breeding” or “Gonna fuck a pup into you.” The clips inevitably ended with the alpha sinking his teeth into the omega’s neck (which looked so fake it got boring fast), saying cheesy lines like, “You’re my bitch now.”

So instead, Dean browsed the Internet to read up a bit on what omegas in heat liked. Those sites, however, weren’t so much about heat sex as they were about taking care of an omega in heat, in between rounds of fucking. Make sure they stayed hydrated, wash their sweat off with a washcloth, cook high-protein meals—that kind of thing. Stuff a mate might do.

Finally, he found an article that first talked a bit about omega anatomy—which Dean scrolled past—and then went on to explain from a medical standpoint why omegas in heat needed the sperm shot as far up their asses as possible. Apparently, that’s where size kinks came from. Dean looked down at himself and shrugged—he’d never had any complaints in that department.

According to the article, omegas in heat also liked getting knotted, but Dean probably wouldn’t do that. Knotting omegas was more trouble than it was worth. It meant that they’d be stuck together after the sex part was over and then what? Small talk while his dick was literally stuck in an omega’s hole had never been his idea of fun. Plus, it was probably too intimate for a first time with an omega anyway.

At least Dean could use the suggestion to use some teeth since omegas in heat liked it a bit rough.

When the day of their heat sex date finally came, Dean felt as prepared as he could be. At least, that’s what he thought…

* * *

As soon as Cas opened the door, the delicious scent of omega slick filled the air. Cas in heat was easily the best thing Dean had ever smelled. But he didn’t have time to enjoy the scent.

Cas, who was wearing nothing more than a bathrobe that wasn’t even fully closed, quickly pulled him inside without so much as a ‘How do you do?’ and let the door fall shut.

Instead of a greeting, the omega asked, reproachfully, “Where have you _been_?!”, which was even more ridiculous seeing as Dean was five minutes early.

The online article about omegas in heat _had_ mentioned irrationality as a common symptom, so Dean played along. “Sorry babe, traffic was a bitch.”

Cas didn’t seem to be listening, though, as he was tugging on Dean’s clothes, snarling when the clothes didn’t come off immediately.

Dean decided to help and as soon as he was shirtless, Cas was on him, scenting along his whole torso, taking in deep lungfuls of his scent. Finally, he buried his face in Dean’s neck and inhaled deeply, letting out a soft sigh as if Dean’s scent alone helped soothe his heat.

Dean’s hands came up of their own accord and he drew the omega in tighter against him, playfully nibbling at Cas’ neck in return.

The tips on how to turn on an omega in heat had obviously been for nothing if the erection peeking out of Cas’ half-open bathrobe was anything to go by, but Dean would be damned if he didn’t try them out anyway. That’s why Dean continued nosing at Cas’ neck, tongue flitting across it and he accidentally licked across his mating gland. When Cas reacted with a full-body shudder, he did it again, this time deliberately, taking pride in the way Cas’ legs buckled and the omega had to hold onto Dean’s arms to stay upright.

Dean slowly unfastened Cas’ bathrobe and let it fall to the floor so that his hands could roam down the omega’s naked body.

“Bedroom?” he asked, so lost in the scent of omega arousal that one-word questions was all he could muster.

Cas, who was currently making short work of Dean’s pants and underwear, motioned towards a door to their right, and Dean, now completely naked himself, steered them towards it, walking Cas backwards as the omega buried his face in Dean’s neck again.

Once inside the bedroom, there was a moment that was a bit awkward when Cas didn’t want to let go of Dean and they fell onto the bed together, Dean on top of Cas, who immediately bared his neck in a submissive gesture that drove Dean’s alpha insane with lust.

Instead of going back to nuzzling Cas’ scent gland, however, Dean dove down to kiss the omega’s parted lips, licking into Cas’ mouth, who eagerly kissed back.

He had never been this turned on in his entire life. With a growl, he broke the kiss in order to flip Cas onto his belly and climb on top of him, rubbing himself all over Cas’ back.

It took him a moment to realize what he was doing: scent marking his omega. He stopped himself—he was going to mark Cas in an even more primal way soon, anyway—and pulled Cas’ ass cheeks apart so that he could stare at the glistening hole he would soon be buried in.

He licked some of the slick that was running down Cas’ thighs off of him and then continued to lick up Cas’ crack. He couldn’t hold back a groan at the delicious taste.

Holding on to Cas’ hips so that he could position him just the way he wanted, he let the very tip of his tongue glide over Cas’ hole.

Cas let out a guttural moan, so Dean repeated the action until Cas started whining, “Deeeaaan!”

“What?”

“I’m in heat,” Cas stated.

“Yeah. I’ve noticed.”

“I need your seed,” Cas said and Dean could practically hear his eye-roll.

Cas rolled over onto his back, showing Dean his belly in submission, a sight no alpha would have been able to resist, especially with Cas’ erection laying heavy against his belly, smearing pre-cum all over it. Dean certainly couldn’t resist leaning down and taking the head of Cas’ cock into his mouth, suckling him in and tonguing at his slit.

Cas let out a whimper, his hands finding Dean’s head, seemingly unsure if he wanted to pull him down deeper onto his cock or push him away.

He ended up pushing him off, and, in spite of Cas’ submissive behavior, he threatened, “If you’re not fucking me soon, I’ll use the bottled alpha seed.”

Dean raised an eyebrow, motioned down towards his own erection and said, “60% more effective.”

When Cas blinked up at him, his eyes a bit unfocused from the heat, Dean took pity on him, scooped up some of Cas’ slick and smeared it across his own erection before spreading Cas’ legs further and pushing the head of his cock into the tight ring before him.

Cas’ eyes rolled back and he let out one of those sexy moans again. Dean was glad that Cas had turned around so that Dean could see his blissed out expression. He usually took his omegas from behind, but right here, right now, he absolutely _loved_ how wrecked Cas looked, drunk on Dean’s cock.

Ever so slowly, Dean forced his cock deeper into the omega’s hole.

Cas was so wet, so slick, yet so tight that Dean had to close his eyes because it felt so good. He could keep his dick nestled inside his omega’s tight little channel for days.

But for now he couldn’t hold back anymore. When he bottomed out, he counted to three inside his head to give Cas at least a little time to get used to the intrusion. Then all bets were off as he pulled back out almost all the way before ramming his cock in again.

The omega mewled, baring his neck in submission, and Dean dove in instinctively, nibbling at Cas’ mating gland, getting another long guttural moan out of Cas who desperately fucked back onto Dean’s cock.

After a few hard thrusts, Cas let out the sexiest sound Dean had ever heard, and Dean grinned as he fucked into Cas again at the same angle, making him quiver in pleasure as Dean laid siege to his prostate.

“Yeah? You like that?” Dean asked, nailing his omega hard. “Want my ‘potent’ cum to fill you up good?”

Cas thrashed around, and for a second, Dean thought he might be trying to get away from the brutal onslaught of his prostate, but his expression was pure bliss and he moaned Dean’s name so sexily, which was permission enough for Dean to fuck him harder.

Cas probably wouldn’t be able to walk for days once Dean was finished with him, which turned Dean on even more, knowing that once he left, he’d leave Cas something to remember him by.

All too soon, Dean felt his knot begin to swell. He usually had more stamina than that, but he had not been prepared for seeing Cas squirming on his cock lost in the pleasure Dean gave him.

When Dean reached down to take Cas’ rock-hard erection into hand and began to squeeze and stroke it in rhythm to his fucking, Cas completely lost it. His cries became wails as he threw his head back and came over Dean’s hand and his own belly.

As Cas continued to shoot stream after stream of thick cum all over both of them, his inner walls tightened around Dean, squeezing his erection so deliciously that Dean could do nothing but fuck Cas through his orgasm and continue to drive into the omega at a punishing pace even after Cas had slumped down into the mattress bonelessly.

Dean’s knot swelled even further and caught on the rim of Cas’ hole. Even though he hadn’t planned on knotting him, it suddenly sounded like an awesome idea.

“Can I…?” he grunted out, barely able to hold back.

Cas wrapped his legs around him in answer, crossed them behind Dean’s back, and drew him in deeper, his head lolling in a nod and moaning, “Please.”

With one last thrust, he pushed his knot in past the rim and tied them together as his cock shot a huge load of alpha spunk into Cas’ channel.

Dean held Cas close, pulling him down onto his cock to make sure he came as deep inside of him as possible. His cock pulsed a few more times as he pumped the last of his seed into the omega, which made Cas’ cock twitch again in response, an exhausted yet pleased moan ripped from his throat.

“God, Cas, you’re awesome,” Dean said blissfully, his voice hoarse from his manly grunts as he collapsed on top of the omega.

He was already looking forward to round two of their heat sex marathon. His dick twitched inside of Cas, agreeing with that sentiment.

As Cas nuzzled into Dean, a fucked out and content expression on his face, Dean couldn’t help but wonder: Why did he suddenly have the urge to go get a bottle of water for Cas? Stupid Internet sites with stupid tips on how to care for omegas in heat…


	5. Chapter 5

Cas woke up to someone probing at his asshole, a finger being gently pushed past the abused rim. He was still loose from the vigorous fucking from before, so the finger slid in easily.

When he turned around and blinked up at Dean, the alpha growled, “My alpha would really like to take your omega again.”

Cas decided that his omega was more than okay with that plan, even though he was still a bit sore from round one and his heat wasn’t quite peaking again. 60% more effective seemed about right. Usually, his cramps would have started up again by now.

Then again, maybe it had something to do with all the water Dean had made him drink or the protein bars he had made him eat… Which had been a bit strange because it certainly wasn’t part of the deal for Dean to make sure he was taken care of. His omega had thought it was rather cute, though.

As Dean continued fingering his hole, Cas could feel himself start to react to the touches and the scent of alpha arousal, and he began to slick like crazy. Seemed like they were up for a second round of mind-blowing sex, which Cas was totally on board with.

Still, the alpha seemed to need it almost as much as Cas, which made him ask, “Is your rut coming on?”

“Nah,” Dean said as he nosed at Cas’ neck. “It’s not due for another few weeks. You just smell so ripe…”

Dean actually growled low in his throat. Cas would have laughed at that if Dean hadn’t found the spot inside him again that made him see stars, so instead of laughing he ended up moaning.

“Can I…” Dean began and pulled his fingers out of Cas’ hole with a slick sound. When Cas looked at him inquiringly, he said, “I really want to mark you.”

“Yes. Please,” Cas said. He didn’t even know if Dean meant scent marking or what—but he didn’t care. Any kind of marking sounded like a great idea to him.

Dean probably hadn’t talked about scent marking, anyway, seeing as their scents were all mingled, and Cas was pretty sure he still had some of Dean’s spunk up his ass since the alpha had shot off so deeply inside of him. Even though Dean had insisted on cleaning him before Cas’ nap, there was no way he had gotten it all out, so technically, he was still marked by the alpha.

When Dean began biting at his neck, the question as to what kind of marking he was talking about was answered. Cas automatically bared his neck again—an instinct he somehow had whenever Dean was coming near his neck—and that seemed to embolden Dean as he began sucking a hickey onto his mating gland.

Cas couldn’t believe he let an alpha play with his mating gland. Encouraged it even. Being an omega, he had been taught to be careful with mating gland play during sex. Accidental matings were a thing that happened in the throes of passion. But right now, Cas didn’t care. In fact, he wished Dean were a bit rougher, would use a bit more teeth. Even while sucking a hickey into such an intimate place, Dean was so damn careful, nibbling almost lovingly at his mating gland.

Cas couldn’t stand the softness, it made him want things. Things that this heat sex date wasn’t about, which was why Cas reached for Dean’s erection and placed the tip of his cock against his dripping wet entrance, shooting Dean an enticing look.

Then he moaned into Dean’s ear, “Alpha. Need you.”

It was only half a lie. ‘Want you’ might have been more honest, but he could almost feel the next bout of heat approach and he was sure it wouldn’t take that much longer for it to start pooling low in his stomach.

Apparently, it was the right thing to say as he could almost see the alpha behind Dean’s eyes, ready to take what’s his. Cas braced himself, but instead of slamming home, Dean was once more slowly pushing into him, inch by infuriating inch, watching Cas’ face for signs of discomfort to make sure Cas was ready for his huge alpha cock. And he sure was well-endowed.

Cas bit his lower lip, trying to look enticing and lure Dean into a kiss as he lay back, Dean towering above him, hands braced either side of his head.

It seemed to work. Dean, still just comfortably inside of him without moving, bent down and licked across Cas’ lips and then into his mouth, playing with Cas’ tongue.

Cas squirmed on his cock in an attempt to get Dean to move. The next bout of heat was finally arriving and he felt himself itch with the need to be filled again. He was slicking even more now, coating Dean’s cock, and he felt so horny he just wanted the alpha to ‘take him’ as he had promised.

“Come on,” he whined when Dean stopped kissing him long enough to let him up for air. “That all you got, big, strong alpha?”

Never insult an alpha’s pride during sex. That was another lesson every omega knew. But somehow, joking around with Dean seemed safe. And fun. Mostly fun.

Dean affectionately rolled his eyes (and _yes_ , finally his hips!) and smiled down at him. “Oh, I see how it is. You’re a little daredevil, aren’t you?”

“I wouldn’t say ‘daredevil’ per se…”

Dean, who had just fucked into him, stopped halfway out to blink down at him dumbfounded. “Did you just finger quote at me during sex?”

Cas squinted up at him. What was wrong with finger quotes?

“Oh, you’re gonna get it now,” Dean growled, still that playful twinkle in his eyes.

“Hopeful-ah!” Cas had wanted to tease back some more, but Dean had finally begun really fucking into him so that he lost the ability to speak and instead had to brace himself.

Dean was so sexy when he let out muffled grunts with every thrust.

Little noises of pleasure were ripped from his own throat as he was penetrated again and again until he felt something besides Dean’s balls slap against his ass. He had popped a knot again. Cas hadn’t known alphas could pop multiple knots a day outside of ruts, but he really wanted it inside of him again.

The first time had been kind of weird once they had been tied together, but then Dean had made some joke and then, it suddenly hadn’t been weird anymore.

“Alpha,” Cas moaned, trying to look as knot-able as possible while being pounded into the mattress.

“Cas!” Dean panted. “Can I…?”

Again with the asking for permission. As if Cas would suddenly refuse his knot.

“Yes! Yes! Yes!” was all Cas could get out around the heat that had spread through his body and was now coiling in his lower stomach and ass, begging for an alpha’s spunk.

He desperately wanted to jerk his own cock, but Dean was lowering himself down on him and then Dean’s belly was rubbing against his cock with every thrust, which was all the friction he needed. When he climaxed, he held on to Dean, moaning the alpha’s name—he could blame the heat for that later if he had to.

And then came the salvation when Dean’s knot slid past his rim and Dean was spilling himself into Cas’ waiting hole. Every spurt of the alpha’s seed brought sweet relief as he felt his heat abate once more.

He had never felt this comfortable during a heat. With a sigh he snuggled down into the pillows, Dean laying down next to him as he positioned them comfortably enough so that they could stay connected while each lying on their own pillow.

The only thing that would make this better would be if they could… touch each other. More so than being connected by Dean’s knot. Not that he wanted to _cuddle_ , but… just being held by Dean would be nice. Maybe have his arms around him and scent his neck or rub their noses against each other…

Sam’s voice floated through his head, then, telling him to give Dean a call if he wanted ‘meaningless heat sex.’ He had known that that’s all Dean wanted going in. There was no way he would ask him for what he wasn’t willing to give.

But maybe he could get Dean to do those things without actually having to ask for them. During the last few hours, he had found out what look to give Dean to get the alpha to kiss him and what look to give him to make the alpha want to knot him.

He just needed to look cuddleable enough for Dean’s alpha instincts to kick in. Only problem was, he had no idea what an omega looked like who wanted to be embraced and held by an alpha.

Blinking up at Dean through his lashes seemed like a good place to start, so he did just that.

“Why are you looking at me like that?” Dean asked, his brows furrowed. Okay, that had clearly not been the right look. “Is my knot uncomfortable?”

No. It actually felt really good inside of him. But that might work as an excuse.

“You know,” Cas said. “It might be more comfortable if we reposition a bit.”

“Reposition?” Dean asked, but Cas was already taking matters into his own hands.

He turned his back to Dean, careful not pull on the knot, and wiggled back against him, taking Dean’s knot deeper in the process and getting another small spurt of semen inside his ass and a groan from the alpha for his efforts.

Dean had no other choice than to place his arms on him or around him, which the alpha did after a moment of hesitation.

Sighing contently, Cas closed his eyes. They’d have a few hours before the next time Cas would need it. Maybe they could continue their discussion from the last time they had waited for Dean’s knot to go down. After all, Cas really liked listening to Dean’s voice.

* * *

Dean mounted him five more times that day. And then there was the time Dean brought him to climax with just his tongue in his ass because, according to Dean, his hole was too fucked out. (Not even Cas’ ‘fuck me’ look had gotten the alpha to reconsider.) After that, Dean brought himself to orgasm and jizzed all over Cas’ ass before he gently pushed some of the seed inside Cas’ hole to alleviate his heat.

In between their fuck marathon, Dean would run the washcloth under cold water and rub Cas down whenever he got too hot and they weren’t quite ready for another round of steamy sex, or get food and water from the fridge (and once from the supermarket across the street).

Cas thought that that was strange for a sex date, but he had never had a casual heat sex date before, so he figured Dean knew the rules better than him. Plus, he was very grateful that he could just stay in bed since he was pretty exhausted.

Cas didn’t want Dean to leave for the night, but he was pretty sure that asking him to spend the night with him when the worst of his heat had already passed was against the ‘meaningless heat sex rules,’ whatever they were.

The next couple days went by in a similar fashion. Cas would pounce as soon as Dean stepped foot inside his apartment and they’d go at it like… well, like an alpha fucking an omega in heat. As his heat was abating, they had less and less sex until Cas wasn’t in heat anymore and was saying goodbye to Dean for the last time.

Cas had no idea if this was supposed to be a one-time thing, and he was trying to think of a way to clear that up, when Dean asked, leaning against the door, “So when’s your next heat?”

“Actually, I’ve been thinking,” Cas said, “This could be a mutually beneficial arrangement.”

He had thought about that during the more lucid parts of his heat and had practiced the speech in his head over and over. There were lots of alphas and omegas who were rut/heat buddies. Cas had just never thought he’d be interested in that. Until now.

“Your rut is coming up sooner than my next heat.”

Dean was rubbing the back of his neck, looking embarrassed of all things, after everything they had done during the last few days.

“Nah, that’s really not necessary,” he said. “Believe me, this already _is_ a mutually beneficial arrangement. And, y’know, I can get kind of rough when I’m in rut.”

Cas thought back to being pounded into the mattress. Walking still felt a bit funny.

“So… That wasn’t rough?” he asked, motioning towards the bedroom where most of their fucking had taken place.

Dean smirked at him, his self-assured attitude returning. “Oh babe,” he said. “That was me being really careful with you.”

Cas wanted to protest that he wasn’t some weak, fragile omega, but he didn’t know if that was just an excuse and Dean simply didn’t want him during his rut. He probably had other omegas at his beck and call. An alpha as awesome as Dean just _had_ to have omegas lining up to spend a night with him.

“Just send me the date of your next heat so that I can clear my work schedule,” Dean said, which made Cas cheer up again. Dean was clearing his work schedule for him.

They awkwardly tried to figure out how to say goodbye—Cas held out his hand, Dean had gone for a hug, then they switched, and finally, Dean simply pulled him forward and pecked him on the forehead.

As Cas watched Dean drive away for the last time this heat cycle, he couldn’t help but feel a bit forlorn. For the first time in his life, he wished that his next heat would come sooner.

**Notes for the Chapter:**

> I hope you liked the new chapter from Cas’ pov?
> 
> I'm looking forward to hearing from you in the comment section. <333


	6. Chapter 6

Never before had Cas been this relaxed after going through heat. Normally, he could hardly get out of bed the day after and had a headache because he had forgotten to drink enough.

He had almost forgotten about Gabe, who came by after every heat to make sure he had ‘survived or whatever.’

As usual, his brother had let himself in and had gone right to the kitchen to refill his fridge and put away some groceries because Cas wasn’t able to go grocery shopping during his heat—only this time, Cas wasn’t lying in bed, exhausted and famished. Instead, he went to the kitchen himself, a bounce in his step, when he heard that Gabe was there.

“Why is there stuff in your fridge?” Gabe asked, his back to Cas, as he was looking into the fully stocked fridge which Cas had Dean to thank for.

Gabe turned around to raise his eyebrows at him, but then his eyes landed on Cas’ neck. “Whoa! Who claimed you?”

“No one,” Cas said as he brushed past Gabe to see if he couldn’t make room in the fridge for what his brother had brought him.

“That huge hickey on your mating gland says otherwise. That’s a big, red neon sign to any alpha you might come across to back off.”

Cas was glad that he had turned his back to his brother because he was pretty sure his face was flaming red. It had been a heat of the moment kind of thing in the throes of passion. It wasn’t meant as a claiming of any sort, but he could see how Gabe would interpret it as such.

When he had looked in the mirror, his mating gland had looked really red and a bit swollen, and Cas had thought about trying to hide the hickey, but he kind of liked it and had forgotten that Gabe would come by…

“Seriously, Cassie—what’s up? I didn’t even know you were seeing anyone.”

“I’m not,” Cas said and slammed the fridge shut. “It was just heat sex.”

His brother gaped at him, opening and closing his mouth a few times. It wasn’t often that Gabe didn’t know what to say.

“ _You_? Heat sex?” he finally managed to get out. “Wasn’t the fact that you didn’t want to have heat sex with Balthazar the reason you two split up?”

“No. That was _part_ of the reason. But he also wanted me to be in a twelve-some with some other omegas, and…”

“Sexual incompatibility, gotcha,” Gabe interrupted him.

Cas rolled his eyes but didn’t correct him. That had not been the reason, but now that he had had Dean and knew what it _could_ be like, he began to wonder…

“So, you gonna see Mr. Heat Sex again?” Gabe asked, waggling his eyebrows.

Cas felt a pang in his chest when he thought about how long he would have to wait until he saw Dean again. His next heat seemed _ages_ away when he was still on his last day of heat leave from the last heat.

“Not sure,” Cas lied because Gabe would totally make a big deal out of the whole thing if he knew.

0

The next couple of days, time crawled by for some reason, and Cas was starting to feel restless. The hickey on his mating gland was fading, which was almost making him sad (even though he had to cover it up when he went to the office anyway), and Dean’s scent around the apartment was getting weaker, too.

Luckily, just as Cas was ready to admit to himself that he kind of missed the way Dean’s eyes crinkled when he smiled, he got a text message from the alpha he hadn’t been able to stop thinking about for the last few days.

**_Dean: did I leave my boxers at your place?_ **

_Cas: Did you really go home commando without realizing it?_

There. Question successfully dodged. There was no way he’d admit that he had stolen them so that he could scent them.

The original plan had been to use them as fodder for getting off, but he had felt too much like a perv to actually go through with it and instead was using them to fall asleep. Dean’s scent was very calming.

God, he was turning into one of those creepy stalkerish omegas—the ones that used their heat to trick an alpha into mating them. The only thing that kept his guilty conscience at bay was the thought that what Dean didn’t know wouldn’t hurt him. It wasn’t like he was going to show up at Dean’s place and present for him or anything…

After that initial question (and the subsequent non-answer), they kind of just kept texting back and forth. The conversation quickly left the topic of advantages and disadvantages of going commando and turned to pop culture, which Cas didn’t know a lot about.

**_Dean: can you believe that dr piccolo is having dr sexy’s pup even tho she’s mated to dr wang?_ **

_Cas: I have no idea who any of these people are, Dean._

**_Dean: you’re joking?!_ **

A few seconds later, his cell phone rang, and that’s how they ended up watching _Doctor Sexy, M.D._ while on the phone. Dean occasionally threw in some facts that were important to understand the storyline—and some tidbits that weren’t really relevant at all, like the fact that the actress who played Doctor Piccolo was actually a beta, not an omega like her character.

Listening to Dean’s voice as he enthusiastically explained all the intricacies of the TV show, Cas felt the restlessness of the last few days leave him. He just smiled contently and threw in a question here or there when Dean was quiet for too long.

0

Dean had managed to hold off for two and a half days, which felt more like two and a half _months_. He just couldn’t forget about Cas, no matter how much he tried. It had been irritating before, when he had first smelled the omega and couldn’t get his smell out of his head.

But now? Not even fucking him (a grand total of 18 times, thank you very much) had helped get Cas out of his mind. Usually, he quickly lost interest in his one-night stands once he had given them a good fucking. But somehow, after their heat sex marathon, he was even hornier than before. Not really in a ‘go out and find some omega to stick it in’ kind of way, but more like… horny for Cas.

He had tried buying synthetic omega scent to forget about how perfect Cas smelled, but the scents that were for sale all made him want to gag.

He was so not an alpha who was daydreaming about a specific omega—except that apparently, he was.

Fortunately, he had left his boxers at Cas’ place on purpose so that he’d have an excuse to get in touch with the omega before his next heat. So he did just that.

He was baffled when Cas didn’t even seem to have realized that Dean had ‘forgotten’ his boxers in his bedroom. Maybe they had slipped behind the bed…

Texting with Cas took the edge off some and talking on the phone was even better, even though he still missed Cas’ scent. Unfortunately, the omega was still as bad at picking up when he was being flirted with, even if he had it in writing.

So, most of his attempts at flirting with Cas via text messages went something like this:

**_Dean: had an omega bring in his car today but he didn’t have blue eyes :(_ **

_Cas: That is a very strange thing to be sad about._

**_Dean: blue eyes are just prettier ;)_ **

_Cas: You should not discriminate between your customers based on how pretty they are or what eye color they have._

Apparently, Cas wasn’t just bad at picking up on body language cues, but he didn’t seem to understand emojis all that well either.

Shaking his head in amusement, Dean was about to text back when he felt his dick perk up in interest.

 _Seriously?!_ Dean looked down at his lap in disbelief. Now he got a boner from _texting_ Cas?

That’s when it hit him—the reason why he had been so horny the last few days. His rut was coming on. A couple of weeks early, what the everloving fuck?

**Notes for the Chapter:**

> Thank you so much for the lovely comments on the last chapter which made my week and which motivated me to write some more. (:
> 
> I hope you liked the chapter, even though I didn’t really get to Dean’s rut just yet. But as you can guess, the next chapter will be about that. I would love to hear from you in the comment section. <333


	7. Chapter 7

Usually, Dean would find his omegas on a website specifically designed for alphas in rut. There were more than enough omegas with a rut kink who were willing to let him go wild and fuck them any way he wanted until they were completely exhausted, almost unable to walk out of Dean’s bedroom once he was through with them.

Most omegas asked him to call them for an encore the next time he was in rut, but Dean never did. He always made it perfectly clear from the beginning that this was nothing more than a way to scratch an itch since his alpha was never satisfied with the less than impressive alternative: using synthetic slick.

He used those omegas and they wanted to be used, so it was a win-win, really. He wasn’t willing to use Cas like that, though. That’s not what they were about. (Apart from the fact, of course, that Cas using Dean’s sperm was what had started it all. But that was different.)

He had already almost lost control with Cas when he had fucked the heat out of him, and Dean was not planning on scaring the innocent omega away by going feral on him during his rut. He wanted to be a gentle alpha for Cas, not a rough one who just wanted to use him as a hole to shoot his spunk into.

Problem was, going online to peruse for some omega ass wasn’t an option this time either, since he felt like he would be cheating on Cas. Sure, they weren’t exclusive, but his alpha couldn’t even stand the thought of being with another omega right now. As a matter of fact, the thought of having some random omega come by for rut sex made him feel sick… kind of homesick for Cas.

That meant that his only option was to use the synthetic slick and his fleshlight, after all.

That worked well enough the first day of his rut. By the second day, however, he felt exhausted and not satisfied in the slightest, even though his balls had produced what felt like buckets full of spunk.

He was so consumed by lust for his ma—for Cas that he felt like howling in despair. Never before had he had a rut that bad.

On top of the emotional turmoil, his dick was starting to seriously chafe. Nothing sounded better than putting it into Cas’ wet channel right now.

Dean knew that alphas who were separated from their omega during rut could end up in the hospital in severe cases. But Cas wasn’t his omega. That thought made him want to curl up into a ball and cry.

A dribble of cum oozed out of his dick even though he hadn’t even touched it, making his balls ache with the need to shoot his seed into Cas.

Some sort of sound made him look around disoriented, trying to discern where it had come from. Ah, he was lying on his bed. The sound had come from his nightstand.

He fumbled with his cell phone and was relieved when he managed to push the right button. Just a text from Sam, asking if he was all right.

Dean was about to put the phone away and wallow in self-pity some more when instead, he somehow pulled up Cas’ contact info. He couldn’t for the life of him remember why he had originally thought it was a bad idea to call him during his rut. It sounded like an _awesome_ idea right now—a way to satisfy a craving that was more important than getting off or pushing his knot into a tight channel.

As soon as Cas picked up, he wailed, “Cas! I need you real bad. Just—please!”

“Dean?” Cas asked, confusion and worry in his voice. “Are you okay?”

“No, I’m really not,” Dean said, even though hearing his… Cas was helping some. But it also made Dean miss him even more. Why were they not together? Why didn’t he have Cas cradled in his arms, scenting his sweet scent?

* * *

Cas hadn’t heard from Dean in a couple of days, which was unusual because the alpha _loved_ texting. He loved it so much that he would text Cas when he saw an awesome car, when he had some gossip to share about Sam, or when something weird had happened on his favorite soap opera (which was basically every day).

Of course, Cas couldn’t admit that he was worried Dean hadn’t texted him back when Gabe asked what was up with him.

Gabe shot him a displeased look. “Seriously, Cassie, are you even paying attention?!”

“What makes you think that I would be interested in why some omega doesn’t want to let you film him during an intimate moment?”

“Because it’s ridiculous!” Gabe emphasized. “ _You_ would let that mystery lover of yours film you getting stuffed by his knot, right?”

“What?! No! And I don’t _have_ a ‘mystery lover.’”

Just then, his cell phone was buzzing, and Cas felt relief wash over him when he saw that it was his—Dean.

It turned out Cas had had every right to be worried. Dean was clearly not all right. He wasn’t forming words, but was making some sort of mating call instead, which made Cas ask, “Dean? Are you okay?”

He ignored his brother, who said, triumphantly, “Oh, mystery lover has a name!” and took a few steps away so that he could focus on Dean instead.

Finally, the alpha managed to switch back to English as he got out, “Rut.”

* * *

Cas’ reassurance that he would be right over had given Dean’s alpha new hope. He began pacing back and forth, then waited by the door for Cas to arrive.

When he did, Dean immediately pulled him inside and shut the door without so much as greeting him, pulling him close so that he could drink in his scent. Only, there was some other alpha scent on him that made Dean wrinkle his nose.

No alpha should leave his scent on Cas! Well—no one but Dean, of course.

Dean quickly went about rubbing his own scent all over Cas, scent-marking every inch he could reach to drown out the other alpha’s scent while simultaneously trying to get Cas out of his clothes.

Once he had managed to get them naked, he lifted Cas up. The omega wrapped his legs around Dean’s waist just in time for Dean to roughly push him against the wall.

He bit at the omega’s neck teasingly and then he couldn’t hold back anymore, searching for and finding Cas’ hole.

As soon as his dick had found its way inside, he grunted and emptied his achingly full balls inside of him, while lapping away at Cas’ mating gland.

The knots inside his stomach started to untie themselves now that he had Cas so close that he was even inside of him, feeling connected to him in every way imaginable.

He pushed his knot past Cas’ rim almost as an afterthought. As much as ruts were all about knotting omegas, Dean had always tried to avoid that part of physical intimacy with other omegas. But he knew from experience that he loved knotting _Cas_ , so his alpha was very self-satisfied when his knot was stuffed snugly inside of him.

He looked into Cas’ face—the omega had closed his eyes and bared his neck—and couldn’t help but mumble, “God, you’re beautiful.”

Cas’ eyes flew open at that and a blush colored his cheeks. “That’s the rut talking,” he said.

Obviously. Alphas didn’t get mushy, especially Dean. They might say stuff like ‘you look knottable.’ But ‘beautiful’? Definitely the rut talking…

Still, Dean felt his chest tighten fondly and quickly dove in for another kiss.

When Cas was starting to get heavy, he decided to carry him to his bed. Cas in his bed—that sounded like an awesome idea!

Once he had carefully lowered the omega onto the bed, careful not to dislodge his knot, everything felt right with the world for the first time since his rut had started.

He didn’t even feel the need to be rough with him or to just pound away. Instead, Dean almost thought it would be enough to lie there, kissing every part of the omega he could reach. He had never felt this at peace and in control of his senses while in rut.

Maybe he could be careful with his omega during his rut after all, and show him how much Dean… liked having him around.

**Notes for the Chapter:**

> I’ve been concentrating on my other fics these last few weeks, but I recently got a comment that reminded me that it’s been a while since the last update here, so I sat down and wrote the next chapter.


	8. Chapter 8

Cas was lying in Dean’s bed, sated and happy next to the sleeping alpha, who had come in his ass twice more after that initial round. They were both naked—no sense getting dressed since there would no doubt be lots more sex before Dean’s rut was over.

Unable to resist, Cas reached over and touched Dean’s face, which looked so peaceful in his sleep. The alpha instinctively sought out Cas’ touch, burrowing closer. Then he put an arm over Cas in his sleep and pulled him close, mumbling something unintelligible in his sleep.

Cas let himself be manhandled, grinning softly at the alpha’s possessive behavior even in his sleep.

Still, Cas wondered if Dean’s behavior was normal for an alpha in rut. Dean had been so careful with him, their sex even more gentle than when Cas had been in heat.

Cas almost regretted that he had never had sex with Balthazar when he had been in rut—maybe then he’d know what the hell was going on here.

 _I can get kind of rough when I’m in rut_ , Dean had said.

Only, Dean wasn’t rough with _him_ , not even a little bit. So, it stood to reason that it was Cas’ fault. He just wasn’t the kind of omega that made Dean lose his mind. Or maybe it meant that Dean was just not that into him.

Just then, Dean began to latch onto his scent gland in his sleep, first scenting, then licking and nibbling while moving his hips against Cas, no real rhythm behind it. Maybe he was dreaming about some other omega. An omega who did make him lose control…

That was it! Cas was done feeling bad about the fact that an alpha in rut had hardly done more than take him missionary style, treating him like a rough fucking might break him. If other omegas could make Dean lose control, then so could he!

It was high time Cas made Dean feel as good as the alpha made _him_ feel. Dean was easily the best sex Cas had ever had—now it was on him to make sure that Dean forgot all about those omegas he usually got rough with during his ruts.

Decision made, Cas climbed on top of the naked alpha, who was making some half-hearted thrusting movements in his sleep, probably still fucking that omega slut in his dream.

Their erections lined up perfectly and Cas started moving against Dean, the delicious friction of their cocks rubbing against each other making him bite his lip to keep quiet.

“Cas!” Dean moaned and for a second, Cas faltered in his movements.

But when he looked down into Dean’s beautiful face, he realized that the alpha was still asleep. Maybe he wasn’t having dirty dreams about some skanky omega after all.

After a while, Cas shimmied down Dean’s body and started lapping at his cock, suckling on the head for a bit and swirling his tongue around it.

Dean moaned a litany of “Oh, yeah! Oh, Cas!” and then began lifting his hips off the bed to fuck into Cas’ mouth.

When his movements became erratic, Cas let Dean’s dick slip from his mouth and placed a gentle kiss on the tip, which was glistening with a mixture of pre-cum and Cas’ spit.

Dean moaned again, this time in frustration as his eyes fluttered open, then flashed red dangerously.

Yes! That was the look of an alpha who was desperate for it.

“Caaaaas!” Dean moaned.

Ignoring the whine, Cas shimmied back up Dean’s body, making sure that the alpha’s dick got a good massage out of it from Cas rubbing himself all over it. Dean bit his bottom lip and closed his eyes in ecstasy.

“I’m going to ride you now,” Cas declared.

Dean’s “Okay” was cut off when Cas took hold of Dean’s erection so that he could slide down until he had taken it all in in one go.

Operation fuck Dean crazy was a go. Cas began bouncing on Dean’s dick, riding the whole length of his shaft. Whenever he felt Dean’s stomach muscles contract in anticipation of spending himself, he slowed down, circling his hips in a figure eight, before riding him to the brink of orgasm again.

The fifth time he had denied Dean the right to pump his spunk into his ass this way, Dean mewled in frustration.

“Yeah?” Cas teased. “Wanna cum in me?”

“Yes!” Dean grunted, trying to fuck up into him, but Cas was having none of it and simply let the alpha’s rock-hard dick slide right out of his hole.

“Come on!” Dean whined, his eyes unfocused. He was desperate, right where Cas wanted him to be.

Cas dove down to suck Dean’s dick back into his mouth like a lollipop, licking their combined tastes off it.

“Fuck, _fuccckkk_!” Dean swore, but the second he tried to fuck his face, Cas withdrew once more, climbing on Dean again instead to ride him some more.

Dean grunted before delivering a heavy thrust, which Cas saw as his cue to slow down their fucking again.

“Cas!” Dean’s high-pitched whimper was like a power rush for Cas. He had reduced the alpha to _whimpering_. “You gotta let me fill your ass, man.”

“Want to deposit your spunk inside of me?” Cas asked, knowing full well that the alpha only had the one thought right now. “Come and get me.”

With those words, he quickly climbed off of Dean. There was a moment in which Cas thought he saw Dean’s eyes flash red again. But the next second, Cas had already jumped out of bed and was racing to the living room.

He had planned to make it to the couch, but Dean caught up with him halfway there, tackling him to the floor with a roar. The alpha immediately started rutting against him until his dick found its way into Cas’ dripping hole, roughly pushing inside until his full length was buried inside of Cas.

The alpha’s mouth found his neck, holding him in place as he began pounding into him with abandon right there on the floor.

 _Finally_ , he was giving control to his alpha. This was what Cas had imagined rut sex to be, Dean’s alpha chasing his omega and making him his bitch.

The display of Dean’s strength was turning Cas on even more.

“Alpha,” he moaned. “Harder! Need you!”

That was the right thing to say, apparently. Dean began really laying into him, fucking Cas into submission. Cas’ prostate had never been so wonderfully abused before. Dean hit it dead on again and again with such force that Cas thought he might combust from pleasure. All he could do was hang on for dear life as Dean fucked into his sensitive core.

Even though Cas didn’t have much wiggle room what with Dean’s teeth holding his neck in place, he tried to bare his neck some more, an instinctual reaction, offering Dean his complete submission and access to his mating gland.

It was all too much as he was getting humped right there on the floor. Cas came without his dick even being touched.

As Cas emptied his balls, Dean bit down harder on his neck, breaking the skin.

Had Cas been in heat, it would have been a mating bite. As it was, Cas’ mating gland hadn’t produced the necessary hormones outside of heat, which meant it was only a claiming bite—and not even one Dean would have put on him if Cas hadn’t made him lose control.

Still—a _claiming_ bite! Cas had never been claimed before. It felt so awesome that he was surprised into spurting out some more cum. At the same time, he felt Dean’s knot being roughly shoved into his poor, fucked-out hole before the alpha pumped load after load of spunk into him, his teeth still holding on to Cas’ neck, making sure the omega took it all.

Once their balls had nothing left to give, Dean licked over the claiming bite gently and pulled Cas against him.

Now that the high of getting the hardest fuck of his life was over, Cas realized that the floor really wasn’t the most comfortable place to lie. But he was tied to Dean and the alpha seemed satisfied in every sense of the word, so Cas just snuggled close and sighed contently.

Both his ass and the claiming bite were throbbing in the best way possible.


	9. Chapter 9

Dean woke up with his back hurting since the position he was in was everything but comfortable. He quickly realized the reason: he was lying on the hard floor.

Cas was pressed against him, which was the only reason he was at least somewhat warm. After all, they were both naked and had no blanket.

Cas was still asleep in his arms and Dean smiled down at him fondly. Then his eyes landed on the bruises all around Cas’ mating gland… and that’s when he saw the claiming bite. As his memories came rushing back, Dean quickly sat up, his dick slipping free of Cas’ hole, which woke Cas up, too.

“Oh my God, Cas. I’m so sorry,” Dean immediately blurted out.

How could he make this right? ‘I lost control during my rut’ was no excuse. He had _claimed_ Cas, without his consent, like some animal.

Cas slowly sat up, too, to squint at him—just having woken up, he probably had no clue what Dean was talking about, so Dean pointed at his neck.

Cas’ hand touched the claiming bite and the frown on his face disappeared.

“You gotta believe me, under normal circumstances, I never would have…”

“Dean, calm down,” Cas interrupted him. “It’s just a claiming bite. It’ll fade.”

 _Just_ a claiming bite? How often had Cas been claimed before?! At that thought, his alpha wanted to come back and take control again, but Dean pushed him back.

Normally, the claimed omega would get mated during the next heat. That’s what a claiming bite was supposed to signify—a promise of a mating as well as a sign to other alphas that this omega was taken.

If the mating didn’t take place, the claiming bite would lose its meaning and fade away like any other mark, leaving the omega free to be claimed and eventually mated by another alpha. Still, you didn’t go around claiming omegas whenever the mood struck. And as an omega, you really shouldn’t let yourself be claimed by just any alpha, no big deal.

“I knew what I was doing when I ran away from an alpha in rut in the middle of sex,” Cas continued. “Believe me, I _wanted_ you to lose control.”

When Dean was still just staring at Cas, shocked by his casual attitude concerning claimings, Cas shrugged his shoulders awkwardly and said, “Don’t worry, I’m not expecting you to mate me. We were just having a little bit of fun.”

Well, good to know where Cas stood. For Dean, it hadn’t just been ‘a little bit of fun.’ Yes, he had lost control, but he had _wanted_ to place that claiming bite on Cas, dammit. So desperately.

Dean had done the rough rut sex a million times with random omegas and it had always been ‘just a little bit of fun’ with them. Never once had he placed a claiming bite on one of those omegas, though, no matter how rough and out of control it had gotten. Never once had he _wanted_ to, either.

“Dean?” Cas asked and Dean realized that he hadn’t said anything in a while. “Are you mad at me for making you claim me?”

“What?” Dean shook his head, more as a way to clear it than as an answer. “Don’t be ridiculous! You didn’t ‘make’ me do anything.”

“Well, I made your alpha chase me…”

“I liked chasing you,” Dean interrupted him. Maybe, since Cas thought it was no big deal, Dean should pretend it wasn’t a big deal for him, either. Deciding to tease Cas a bit to show how cool he was with everything, he said, “Of course, you never stood a chance of getting away…”

It worked like a charm. Cas scowled at him and immediately retorted, “I wasn’t _trying_ to get away.”

Dean shrugged. “Doesn’t matter. I would have been faster either way.”

“Oh, you think so?”

“I know so. Don’t take it personally, I’m just a really fast alpha. Give me the right incentive and I’d be able to catch anyone.”

And Cas was _definitely_ the right incentive.

“Want to go again?” Cas asked and without waiting for an answer, he added, “First one to the bed wins.”

With those words, Cas, that feisty little omega, dared to run away from him. _Again_!

It only took Dean’s alpha half a second to take over and give chase, even though he had just had a wild round of rough sex that should have kept him appeased and under Dean’s control for a while.

Cas had made it to the bed, sitting propped up against the headboard and looking so smug that Dean just pushed back inside of him in one punishing thrust. The omega’s hole was still loose and fucked open from before, which was a good thing because Dean hadn’t given him any time to slick, just pumped in and out of him a few times before reigning in his alpha.

“You have to stop running away from me while I’m in rut!” Dean admonished once he was in control again, his dick still nestled inside Cas’ comfortable hole. Really, his alpha had no business needing it again so soon.

Usually, the urge to fuck came and went for alphas in rut in intervals of several hours. Maybe Dean’s alpha was so oversexed because he couldn’t knock up Cas, since the omega wasn’t in heat. (Not that that had ever bothered him with any of the other omegas before.)

Dean’s dick twitched inside of Cas, ready to pump his omega full of another load, and it took everything Dean had to hold back.

Cas didn’t seem to mind. He was looking up at him seductively, letting himself be held down, _enjoying_ being dominated by Dean. So much so that his eyes flashed golden.

This was why a claiming bite was not ‘just a bit of fun.’ Cas’ omega and Dean’s alpha had already started their little mating dance, checking each other out, apparently deciding that they liked what they saw. They were obviously compatible for mating if the way they got lost in each other while fucking was anything to go by.

It would drive Dean’s alpha _crazy_ not being able to mate this omega during his next heat. It would drive _Dean_ a little bit crazy, too, probably.

Possibly.

Totally.

Dean swallowed as he stared at the claiming bite, licking his lips. It looked sexy as hell on Cas. Marked for mating by Dean.

 _Just a little bit of fun._ Ha! Dean would make sure that _this_ was a claiming Cas was sure to remember for a long time.

“Last chance to say no,” Dean rasped, feeling the reigns he had on his alpha slip through his fingers quicker than expected. “Or prepare to be fucking _wrecked_.”

Cas looked at him all wide-eyed, but Dean knew it was a look of anticipation. The omega had urged him on, had _wanted_ it as hard as Dean’s alpha needed it. He had taken the brutal fucking so well as if his hole had been _made_ for Dean’s prick to fill.

“What’re you waiting for?” Cas’ challenging voice brought him out of his thoughts.

That flippant remark was all it took. Dean didn’t think he could have held back his alpha any longer if he had wanted to. He snapped his hips forward and immediately began drilling into the omega at a vicious pace, fucking groans and moans out of him.

Cas’ omega had caught up with the proceedings, finally realizing that his hole was going to be fucking _owned_ by Dean, and then wet slick was coating Dean’s dick. The omega juices smelled so delicious it only made Dean take the omega harder, making sure his hole would feel nice and sore after.

Cas’ face was contorted in ecstasy and Dean loved drinking in his expression, seeing how much pleasure he brought him, but he also wanted to take him bitch style again. So, Dean pulled his cock out of the warm, wet cock heaven it had been in with a slurping sound and made Cas turn around. The omega seemed a bit dazed, not quite comprehending what was going on, but that was what he got from goading Dean.

He slapped the omega’s ass and luckily, Cas interpreted it correctly, which was a good thing because Dean didn’t think he could have formed complete sentences. The omega got on his hands and knees and raised his ass so high that Dean got a good view of the pink hole, which was now gaping, slick and some of Dean’s come from before dribbling out of it.

Dean forced his ass cheeks further apart to have full access to the beautiful fuck hole so that he could feed his cock into it again.

Cas moaned long and loud as his ass swallowed Dean’s dick once more.

Dean had to close his eyes and keep himself from moving for a second so that he wouldn’t immediately empty his balls into Cas’ channel.

They just _fit_ so perfectly. This was what had missed with all the other omegas. Yes, he had fucked them good, too, but he had mostly just gone through the motions, letting the friction of his dick in some omega pussy coax the spunk out of him. With Cas, the thought of _having_ the omega, marking him all over, making him mewl in pleasure, making him _Dean’s_ —that was what drove his alpha wild.

From this vantage point, the claiming bite was clearly visible, and Dean bent down to nibble at it, reminding Cas who he belonged to, if only for the moment.

“Dean!” Cas moaned, pushing his ass back against him, silently urging him on to make him his bitch once more.

And Dean’s alpha was more than willing to oblige. This omega was _his_ , dammit! And Cas better believe it.

Picking up the pace and thrusting erratically to make sure Cas wouldn’t be able to get out of bed later let alone walk around, Dean felt his balls tingling and knew he was close. God, he wished Cas was in heat, so that him pumping his omega full of seed wouldn’t go to waste.

Under him, Cas was busy fisting his own prick, his ass muscles clenching and contracting, giving Dean’s dick a good massage.

Cas’ claimed mating gland looked so good, _tasted_ so good that the moment Dean pushed the whole length of his cock, including his knot deep into the omega and emptied into him, he bit down on it again, making sure Cas knew just who had a claim on him.

A second claiming bite was unusual to say the least, but Cas seemed to like it as well if the way he shouted out and came all over the sheets was an indication. Dean had never had sex with an omega as responsive as Cas before. He wasn’t even in heat and could keep up with Dean’s insatiable sex drive during rut.

Dean just fucked Cas through his orgasm even when the omega’s legs gave out under him and he sank down onto the bed, completely boneless.

Once Dean had pumped Cas full of as much spunk as possible, he collapsed on top of him, blanketing the omega with his own body.

Dean’s alpha was very satisfied with the sight and scent presented to him: sated omega after getting the ride of his life, marked by Dean’s teeth, dick and spunk, completely defiled and ruined for any other alpha.

How about that for ‘just a little bit of fun.’ Dean was pretty sure no other alpha had ever claimed Cas this thoroughly before.


	10. Chapter 10

Cas began to realize why Dean had warned him about being rough. His ass wasn’t getting any reprieve. That alpha had stamina, for sure. His rut just went on and on and there was hardly any time when the alpha’s dick wasn’t busy defiling his hole.

His ass must have been fed more alpha spunk in the past few days than in his entire life up to Dean’s rut. It had certainly never gotten such a vigorous workout before. It got to the point where it felt empty whenever Dean’s dick _wasn’t_ fucking into it.

Cas had noticed that whenever he touched his claiming bite, Dean’s eyes would flit to it, and then his pupils would flash red again and Cas would get another rough banging.

So, naturally, he touched his claiming bite _a lot_.

His omega _loved_ riling Dean’s alpha up and then having the alpha assert his dominance over him until there was nothing Cas could do but let his omega instincts take over and submit. Baring his neck, showing his alpha his belly, holding back his own ass cheeks so that Dean could fuck his huge alpha prick into his depths…

He also loved fighting with Dean in a playful way and resisting submitting to him for as long as he could. What he loved more, though, was losing that fight—when Dean had inevitably had enough of Cas’ antics and would just hold him in place while fucking him, either by keeping his teeth on Cas’ neck as a warning or by gripping him tight so that Cas couldn’t move, and forcing him to just _take_ it.

Rationally, Cas knew that the claiming bite didn’t really _mean_ anything—alphas in rut just liked claiming the closest omega they could find and Cas was pretty sure he wasn’t the first nor the last omega Dean would claim in the throes of passion. Still, he enjoyed the illusion of being Dean’s, and positively reveled in the alpha’s possessive behavior, even if it was all just a symptom of his rut.

They tried taking showers in between to get rid of the smell of rut and sex, but Dean would just end up taking him against the shower wall. Seriously, how much semen could one alpha in rut produce in as many hours?! Cas didn’t complain, though, since he loved the feeling of Dean’s hot sperm flooding his ass, shooting spurt after spurt deep into him in an attempt to fill up his womb to the brim.

When the rut finally came to an end, Cas could barely think straight. He was just lying on his alpha’s bed, exhausted and filled up with alpha spunk.

Dean gave his ass a final half-hearted slap before pulling out of his abused hole for the last time, sighing contently.

Then he bent over, kissed the claiming bite gently and pulled Cas snug against him.

“Best rut ever!” he declared, which made Cas’ heart do a flip-flop thingy, even though he tried to tell himself that Dean might very well be saying that to all of his omegas once he was done with them.

Pretending for a moment longer, Cas let himself be held and snuggled by his alpha.

Eventually, it was time for Cas to go home.

Leaving these days of pure bliss behind was strange and felt as if he was leaving his mate. Damn claiming bite, still making him think of Dean as ‘his’ alpha.

When they were saying goodbye, Cas awkwardly mentioned the date when his next heat was due. Thinking that he might not see Dean until then was making both him and his omega want to howl in frustration.

Dean rubbed the back of his neck and looked at the wall, which in return made Cas narrow his eyes. If Dean thought he could just send Cas away for good now that he had gotten his, Cas would so punch him in his handsome face, alpha or not.

“I’m gonna be honest here,” Dean began, his eyes finding Cas’ again shortly before they settled on his neck. “I don’t think I’ll be able to keep my alpha from mating you if we meet up for your next heat. Once the claiming bite has faded…”

“I’ll wear an anti-mating collar then,” Cas interrupted him.

He was pretty sure he wouldn’t be able to deal with being left alone for his next heat. Not now that he knew what he could have. Not now that his omega was already going crazy just thinking about being separated from his—from Dean.

Dean smiled and reached out, about to touch the claiming bite, but he aborted the gesture halfway and let his arm fall back to his side. “That’d probably be for the best.” Then his smile turned mischievous and he added, “In that case, I’m looking forward to it.”

This was accompanied by his signature wink, which Gabe had told him was a flirtation. Cas had no idea why Dean would be flirting with him now that he’d had Cas in every way imaginable and they had just made plans for heat sex again. There was no need for Dean to try and charm him into his bed anymore.

Still, not wanting Dean to think that Cas wasn’t receptive to his flirtation, he winked back, which brought Dean up short.

The alpha blinked at him dumbfounded a couple of times and Cas was starting to wonder if his wink had been incorrect. How many ways were there to wink anyway? You just closed one eye and then opened it again—right? He knew he sucked at flirting, but this seemed a pretty standard technique that even he shouldn’t be able to mess up.

Before Dean could mock him for his inability to flirt, Cas quickly said goodbye and carefully walked to his car, each step a reminder of what he had spent the last few days doing (and _who_ had been doing him).

* * *

When Gabe stopped by for one of his impromptu visits, his first reaction upon spotting Cas’ claiming bite—or rather claiming _bites_ —was, “You’ve certainly gotten around since we last spoke.”

“It’s from the same alpha, jackass,” Cas retorted and touched the claiming bites. He hadn’t been able to keep himself from fingering them since he had left Dean’s place.

“An alpha claimed you _twice_?” Gabe asked, wide-eyed. “Heat sex guy?”

When Cas nodded, unable to suppress a small smile thinking about Dean, Gabe whistled and said, “Boy, he must really want you bad, huh?”

The smile fell off Cas’ face and he exaggeratedly rolled his eyes. “No, he doesn’t. He was just in rut and lost control.”

“Cassie.” Gabe put a hand on his shoulder and looked at him with his ‘I’m your big brother and know so much more about the world than you do’ look. “Take it from an alpha. If an alpha claims you _twice_ , in rut or out of it—that means he’s sweet on you.”

Then he let go of Cas to flop down onto the couch, pulled out a lollipop and began munching on it. “So, should I get ready for some nieces and nephews?” he asked as he was making himself at home, his feet on the table and a twinkle in his eye.

Cas tried to fight the blush he felt spreading across his cheeks. “I wasn’t even in heat!” he said, only realizing a second too late that the denial had been a bit too forceful.

“Oh, wow.” Gabe almost dropped the lollipop as he sat up at attention. “That was a joke, but from your reaction I’m thinking I really should start planning a pup shower.”

“It’s not… Dean and I aren’t… like that,” Cas tried to explain. He remembered the way Dean had freaked out as soon as he had realized that he had accidentally claimed him.

“All I’m saying is, alphas don’t claim omegas because they ‘lose control.’ They claim them because they want to, you know, _claim them_. Believe me. I’ve lost control plenty of times during my ruts.”

“Gabe!” Cas exclaimed. He really didn’t want to hear what his brother got up to during his ruts.

Gabe just spread his arms and concluded, “Still free as a bird. Haven’t claimed anyone yet. So, if he didn’t want to claim you, you wouldn’t be sporting two claiming bites right now. Just something to think about.”

Cas was almost starting to think his brother wasn’t the worst option to talk to about this alpha stuff, when Gabe had to ruin it by saying, “So, when do I get to meet your mate-to-be?”


	11. Chapter 11

Dean had feared that things might be weird between them after he had given Cas’ hole the pounding of its life. He had watched Cas walk funny to his car and part of him—the alpha part that was oh so proud that he had claimed the omega—had enjoyed knowing that Cas was sure to remember this fuck for a while.

Another part of him was still a bit embarrassed. He had been so rough with his innocent little omega. Well, Cas certainly wasn’t innocent anymore. Although Dean tried to tell himself that Cas had been the one to initiate the out-of-control fuck session, so the jury was still out on exactly how innocent the omega had been to begin with.

In any case, Dean had picked up their texting the very next day, asking how his ass was (smooth!) and what was new (probably not a lot in the 24 hours since they had last seen each other).

The weirdest thing about it all was that things between them _weren’t_ weird.

After texting back and forth for a while, Dean finally sent, ‘im bored. wanna hang out?’

Half an hour later, he was balls deep in Cas again. That hadn’t been what he had meant when he had asked the omega to come over, but Cas had basically taken off his shirt the minute he had walked in the door.

It wasn’t like Dean was complaining or anything. What kind of an alpha would he be if he complained about getting too much omega ass? Plus, the claiming bite was still a huge turn on, even out of rut.

At least now that Dean’s dick wasn’t able to go again immediately after unloading its juice inside Cas, he got his chance to hang out with the omega just because. They made some popcorn and watched a movie, and Dean couldn’t help but think how mate-y this all was, especially when he glanced at Cas and his eyes automatically found the claiming bite again.

During the next weeks, they got into the habit of meeting up for sex whenever one of them asked the other if he had time. At least the evenings always started out with a roll in the sheets. Afterwards, though, they would get up to all kinds of things.

Either they stayed in, talked for hours, cooked and ate together, watched TV… Or they went out for a walk, to a restaurant, to the bowling alley…

It was on a Saturday afternoon when they had met for a quickie and then went to a diner after, when the waitress said, “Congrats,” nodding towards Cas’ neck. She clearly thought they were a couple, engaged to be mated. That’s when it dawned on Dean: He was kind of courting Cas. Taking him out, showing him a good time…

He couldn’t even remember the last time he had fucked an omega other than Cas, and more so: he couldn’t even remember _wanting_ anyone else but Cas.

“Dean, you okay?” Cas asked, a worried crease on his forehead.

“Whu?” Dean made, completely caught off guard by his realization.

“I can wear a turtleneck if it’s making you uncomfortable,” Cas offered, having interpreted Dean’s freak-out wrong.

“Nah, I’m fine,” Dean quickly said.

His alpha had clearly started courting Cas without Dean’s permission. Question was, was Dean willing to let it go on? To maybe even step up his game? To show Cas that he could do more than just sex him up real good?

Okay, that was not really the right question. The question was _how_ did he get Cas to see him as more than a fuck buddy he just had some fun with? How could he make the omega appreciate him for more than his spunk?

How did alphas even go about courting omegas?

He wasn’t the kind of alpha omegas were interested in starting a serious relationship with. His good looks got him laid whenever he wanted to, sure, but he had no experience when it came to long-term relationships. After all, he hadn’t ever been interested in dating before.

Looking at Cas, who was doing his head tilt thingy as always when he was trying to figure Dean out, he realized that yes, he absolutely one hundred percent wanted this omega—and only him.

* * *

Dean’s attempt at courting Cas did not go too well.

He tried walking close to Cas, maintaining contact as much as possible, but the omega didn’t seem to even notice, which was most likely due to the fact that Cas himself had no concept of personal space.

Next up on the list of tips he had found online: intense eye contact. Again, Cas seemed unfazed. They had been staring into each other’s eyes a lot, anyway, so nothing new there, either.

He tried grooming Cas, fixing his tie and collar, but Cas thought he was trying to get him out of his clothes and promptly helped loosen the tie instead. (Again, Dean wasn’t complaining when moments later, Cas was on his knees, naked, suckling on Dean’s cock.)

Which brought him to the most frustrating thing of all: every time Dean tried to set up a romantic date, they ended up having sex. Which was awesome, of course, but it also sent the wrong message. Even though they went out after they fucked, the reason for meeting in the first place stayed the same no matter how Dean phrased his invitation.

He would have to be less subtle if he wanted Cas to see that he had romantic intentions towards him. That’s why Dean was out grocery shopping because he was planning on inviting Cas over so that he could cook for him. A dinner by candlelight with some nice music would set the mood and send the right message for sure.

He was looking for a nice bottle of wine when he saw Cas at the other end of the aisle with some alpha. The alpha was smaller than Cas and had his hands all over him.

What kind of an alpha was trying to pick up an omega who had very clearly been claimed by another alpha?! Of course, Cas, being his oblivious self, didn’t even notice that the alpha was all up in his personal space, coming on to him.

Before Dean could talk himself out of it, he was walking towards them briskly, but by the time he had made his way to the end of the aisle, Cas had scurried off somewhere.

“Hey, buddy,” Dean said, catching the attention of the short alpha, who raised his eyebrows at him. “Don’t know if you realized, but that omega you were feeling up is already claimed.”

The alpha looked him up and down. “Yeah, I realized,” he finally said with a shrug, his devil-may-care attitude pissing Dean off even more. “Going after claimed omegas is half the fun, don’t you think?”

Dean ground his teeth in an attempt to stay calm. Getting into a fight with some knothead alpha in the middle of a supermarket would only get him arrested.

“He has a great ass, huh?” the alpha went on and that was _it_. Dean saw red. He didn’t care if he was being rude, he bared his teeth at the other alpha.

But before he could tell him off, Cas came back.

“They are out of—Dean! What are you doing here?”

“Shopping, one would assume,” the alpha mumbled, but Dean ignored him.

“Hey, babe,” he said, smiling brightly and walking over to plant one on Cas, tongue and all, the kind of kiss that was completely inappropriate for public places. He made sure to brush his thumb over Cas’ claiming bites for good measure, satisfied when Cas bared his neck for him right there in public and in front of the alpha jerk.

Then he took Cas’ hand and pulled the confused omega away from the alpha, leaving his own shopping cart behind. For some reason, the alpha was watching them with a mischievous glint in his eyes.

Once out of earshot, Dean warned Cas, “That alpha is bad news. I know you don’t pick up on these things, but he was clearly hitting on you.”

Cas squinted at him and then deadpanned, “That’s my brother.”

“Your _brother_ was hitting on you?!”

“He was _not_ hitting on me.” After a moment of contemplation, Cas added, “You are right about the ‘bad news’ though.”

“He was _touching_ you.”

“Again. He’s my brother. He’s allowed to touch me.”

Upon further reflection, maybe his hands had not been _all over_ Cas, but it might just have been a hand on his arm, which Dean’s alpha might have taken the wrong way.

“He told me you have a great ass,” Dean pointed out, still trying to figure out if the alpha really was no danger to his claim on Cas. “What kind of alpha says that about his brother?”

Cas rolled his eyes. “Riling up other alphas is kind of what he does when he’s bored.”

That’s when Cas’ brother stepped out from behind a shelf. “I couldn’t help but eavesdrop…” Dean snorted. “…but you were really easy to rile up,” the alpha continued, a smirk on his face.

“This is my brother Gabe,” Cas said, motioning towards the alpha. “And that’s Dean, my…” He trailed off and then simply repeated, “That’s Dean.”

Dean smirked back and then somehow found himself in a smirking contest with Gabe.

He got it. Telling your brother, _That’s the guy I have kinky sex with,_ was probably not the best idea. But Dean was still curious to know how Cas would have ended that sentence. _My alpha._ That’s what Dean would have liked to hear, but probably not what Cas had intended to say.

Dean wondered if Cas had told Gabe anything about him at all.

“Uhm… okay then,” Cas said, looking at Dean warily, and Dean realized that he was still smirking at Gabe, which might come across as weird by now.

“So, what are your intentions…” Gabe started, but Cas took him by the sleeve and dragged him along.

“Aaand we are really late,” he called back to Dean. “Text me.”

Dean was left staring after them. Damn his alpha for thinking Cas was his omega to protect!

Back to the task at hand. The romantic dinner was still his best bet at getting Cas’ omega to maybe start seeing Dean as his alpha, too.


	12. Chapter 12

Cas knew by now what an invitation to ‘dinner’ was code for. He was either the appetizer or the dessert. Of course, he _loved_ being devoured by Dean, but somehow, that wasn’t enough for him anymore.

They had proved again and again that they were sexually compatible. But they had done lots of other things together that secretly, Cas liked to think of as ‘dates,’ even if Dean would laugh in his face for saying it out loud.

With Dean’s kind of sex drive, Cas had no idea if maybe he had a few omega side dishes. They hadn’t talked about being exclusive after all. That’s why Cas had tried to fuck Dean to exhaustion whenever they met, so that his alpha wouldn’t go looking for other omegas.

But then Dean had reacted rather possessively towards him in the supermarket and Cas thought that maybe it was time to have that talk about exclusivity.

So, when Dean invited him over for ‘dinner,’ Cas planned to broach the subject, preferably before they ended up in bed together again.

He was encouraged when Dean led him to the living room and he took in the dimmed lights and candles adorning the covered table. There was music playing softly in the corner and it smelled delicious. Dean had obviously put a lot of effort into cooking for him.

When they started eating, they chatted idly for a while and Cas tried to find the best time to bring up their arrangement. When their conversation came to a natural pause, Cas thought he had found his opening.

Before he could get up the courage to do it, though, Dean cleared his throat.

“So…” he began. “The sex is great. Obviously.” He looked at Cas as if waiting for confirmation, so he nodded his agreement. “And you’re funny and cute and fun to hang out with. I kinda like you a lot.”

Cas felt warmth spreading from his chest to his cheeks and smiled shyly down at his plate. Only then Dean said, “But…” and trailed off, and just like that, the warmth was replaced by a sudden chill. There was a ‘but’? Cas had thought this was going well, and now there was a ‘but’?

“Well, you know…” Dean continued. “The arrangement wasn’t really supposed to be a permanent one…”

Cas’ stomach was tying itself into knots and he put down the fork, suddenly not hungry anymore. Was Dean trying to let him down gently? What kind of an alpha set up a romantic atmosphere to break up with someone?

Cas knew what kind. The kind who didn’t even like omega-flick moments and had no clue about romance! The kind who had been open and honest about the fact that he was using omegas for sexual gratification only. Just because this was getting too real for Dean, he preferred to break things off?

Even though he was starting to get a bit mad at Dean (how dare he? They had something good here!), Cas’ mind was still trying to come up with arguments for why they should continue their arrangement. Maybe Cas should distract the alpha by presenting for him. Dean never could resist fucking him when he presented for him.

“But then you went and had to be all… _you_ ,” he heard Dean say, but at this point he had stopped paying close attention, too busy thinking about what to do or say next. “So I guess what I’m trying to say is… Maybe we should make this arrangement more permanent?”

“Let’s have sex!” Cas blurted out. “You can spank me with your dick and I’ll wear the cowboy hat.”

“Uhm…” Dean blinked at him. “So that’s a no then?” Then his face shut down into a blank mask. “Yeah, you’re right. Was a stupid idea. Just forget I said anything.”

“What idea?” Cas asked, trying to replay in his mind what Dean had said while he had been freaking out. The words ‘more permanent’ reached his brain only after he’d already put his foot in his mouth. “More permanent?” he repeated out loud.

“Like I said. Was just a stupid thought that crossed my mind. Doesn’t matter.” A faux-casual shoulder shrug accompanied that statement.

The warmth rushed back. Dean didn’t want to break it off. He actually wanted the same thing Cas did!

“We should be exclusive!” he exclaimed what he had wanted to say the whole time.

Dean didn’t look too enthusiastic about that prospect, which left Cas confused. Wasn’t that what ‘more permanent’ had meant?

“You’ve been sleeping with other alphas?” Dean asked, voice low.

“No! I just… don’t want you to sleep with other omegas either,” Cas explained.

Finally, a smile returned to Dean’s face. “Haven’t done that since the first time my alpha had a go at your omega.”

Cas smiled back, relief washing through him. “So, more permanent?” he prompted.

“More permanent,” Dean confirmed.

* * *

Dean hadn’t really gotten Cas to agree to being his omega, but the date night had been a success anyway. He could live with an exclusive, ‘more permanent’ arrangement for now. After all, he wouldn’t have to worry about other alphas sniffing around Cas, since he now had some sort of claim over him.

Knowing that his spunk was the only one making it inside of the omega’s hole was appeasing his alpha due to biological reasons. Plus, it meant he was able to keep the omega sexually satisfied, which was always important for an alpha.

Knowing that Cas wasn’t interested in sleeping with any other alphas put Dean into a good mood. It meant that the claiming bites on Cas’ neck, which were only slowly fading, were more meaningful than Cas had originally let on.

Dean had totally claimed that omega. Not just because their sex had gotten a bit out of control, but as a suggestion for a ‘very permanent’ arrangement.

From then on, the dates they went on didn’t necessarily have to conclude (or start) with Dean fucking Cas. They still did more often than not because those claiming bites hadn’t lost their appeal and Cas always smelled too delicious to resist, but sex wasn’t the reason for why they met up anymore.

As always when things were going great, time just flew by, which was why it was a bit of a surprise when the calendar said that Cas’ heat was only days away.

One thing Dean was really excited about was mating role play. He’d fantasized about mating Cas _a lot_ and when he had brought up the role play idea once during sex, Cas had said that they should wait for his heat since it would be more realistic then.

He simply couldn’t _wait_ to fake-mate Cas.


	13. Chapter 13

If Dean had thought the last time Cas had been in heat that there was no better smell in the world, he had been wrong. Last time, he hadn’t even really known all that much about Cas, had mainly been attracted by his scent and good looks and the need to get that omega naked and under him as soon as possible.

Now, though… Now, it was the scent of _his_ omega in heat, and that was a whole new scent experience. Since Dean had never claimed an omega before, he had never known how intoxicating and arousing the scent of an omega was when he was wearing his claiming bite, prepped and ready to be mated.

As promised, Cas was wearing an anti-mating collar, which was a bit disappointing because Dean couldn’t even see his claiming bite. Still, seeing Cas on his knees, naked save for that collar was a turn-on in and of itself. After all, it was a reminder that Cas _could_ get mated right now.

Dean’s dick agreed, twitching with the need to fuck Cas’ little hole in preparation for their mating. Fake mating, Dean reminded himself, but of course, his dick (and heart) didn’t care for the distinction.

Cas, who was a handful in bed even when he wasn’t in heat, seemed to need it bad. He was urging Dean on when he took a minute to take in the beautiful sight in front of him and started begging so prettily as he went down on his elbows and presented his ass for the taking.

When he even reached back to pull his ass cheeks apart in invitation, Dean gave in and pressed the seeping tip of his dick to Cas’ defenseless hole, about to commence the mating process.

He couldn’t have held back a possessive growl if he had wanted to when he pushed inside, feeling Cas’ inner walls quaking as they clenched around his thick length, trying to accommodate the intrusion.

Dean held back, drawing out the moment of penetration because it just felt so damn good! The moment Cas submitted to his alpha sexually, completely at Dean’s mercy, gave him such a power rush that he felt his member throb in anticipation, impatient to spurt his seed into Cas’ sopping hole.

Finally, Dean’s cock bottomed out at Cas’ cervix. A wanton whimper escaped the omega’s lips, which told Dean that it was time. All the sex they’d been having meant that Dean knew exactly what to do to drive Cas wild.

So, he grabbed a fistful of Cas’ hair and pulled his head back so that his back arched and began to fuck him as hard as he could, riding him like a bronco.

The sounds of their moans filled the air, interspersed with the wet slaps of Dean’s cock dominating Cas’ hole.

“Dean! Now! _Now_!” Cas begged, so Dean slapped his ass, leaving a red hand mark, while he continued to drive his cock into him, fucking the orgasm right out of the omega.

His own balls were so full and tight, he couldn’t wait to empty them. This fertile little omega was about to get pumped full of sperm all right.

God, how he wanted to lick and bite at Cas’ neck! Only the damn collar was in Dean’s way. He nuzzled behind Cas’ ear instead, growling at the collar as his hips stuttered in their rhythm. Licking all around the collar, he tried to slip his tongue underneath it, but it was too snug.

“Mate me!” Cas begged.

“I’m trying!” Dean shot back, but at that moment, Cas twisted to look over his shoulder, giving Dean’s dick just the right kind of friction to start spewing out a flood of jizz.

Cas’ greedy little hole swallowed it all as waves of pleasure kept rolling through Dean’s body. His knot had popped outside of Cas’ hole, but that was okay—there was enough time for knotting later.

Dean pulled on Cas’ hair again, this time to get him to turn his head so that he could lick into the omega’s mouth. This wasn’t just about heat sex. This was about _them_. This was about what they felt for each other. And if Dean had an easier time expressing that by giving Cas a good pounding, well… Then at least they got some awesome sex out of it.

Afterwards, Cas was laid out on the bed, defenseless and defiled, his hole already turning red from just one round of fucking. The sight was enough to make Dean’s cock twitch.

That was too soon. It should be sated after the amount of spunk it had just unloaded deep within Cas.

Those were the first signs of rut. Cas’ heat had to have sent him into rut. It shouldn’t have happened, it was too soon for his next rut. That’s what happened to _mates_. But it would actually be easier if their cycles synched, even if they weren’t mated. Which reminded him… Now that the first wave of heat was taken care of…

“So. The collar kind of puts a damper on the whole mating role play,” he mentioned casually.

Cas yawned and turned around under Dean so that he could snuggle up to him. “You’re the one who insisted on it.”

What? “Uhm… I’m pretty sure _you’re_ the one who brought it up.”

“As a compromise. After you tried to dump me.”

“I didn’t try to…” Realizing that they’d go in circles arguing like this, Dean settled on a different approach. “Where am I supposed to fake-bite you if I can’t even get to your neck?”

“Keys are in the bottom drawer,” Cas said, motioning to the nightstand. “Now let me refuel my energy before your rut starts and my next bout of heat comes in.”

Of course, nothing got past Cas. He had to have already scented the beginnings of rut on him. Dean quickly dove for the bottom drawer, almost falling out of bed in the process, and fished around for the keys so that he could get that collar out of the way.

In his haste, he almost didn’t find the lock, but then—finally!—the collar came off with a click and Dean threw the offensive item onto the floor.

The claiming bites were still there, not as red anymore, but still oh so beautiful. Dean stroked over them lovingly before he nuzzled into Cas’ neck, taking in the awesome scent first-hand.

He felt his body thrumming with the need to mate Cas. But maybe he should recharge his batteries too. After their nap, the games would start…


	14. Chapter 14

When Dean woke up, his rut had hit, meaning that it was time for Cas to get his ass creamed again. And he would get a huge load if Dean’s horniness was anything to go by.

First, he’d have to make sure they were on the same page, though, by making the omega slick so much he’d be begging for Dean’s spunk.

Turning the sleeping omega over onto his belly, Dean shimmied down so that he could take a look at that asshole he’d been pounding into not too long ago (and the one he’d be pounding into soon enough again).

He inserted a finger and probed his hole, satisfied when he found some of his jizz still in there. Breeding instincts were awakened when in the presence of an omega in heat—especially if he himself was in rut and especially if the omega in question was wearing his claiming bite—so knowing Cas’ hole was still full of his fuckjuice turned him on like crazy.

With Cas being at his most fertile, giving off a scent that was supposed to attract alphas and make them breed him up, Dean’s alpha wanted nothing more than to do just that. Every instinct in him was telling him to breed this cute little thing.

But before Dean would plunge his dick into Cas’ fuck hole again, it was time to rim that asshole until it was dripping wet to make Cas delirious with lust for another load. Sucking his own spunk mixed with Cas’ slick out of his hole made him even hornier—seriously, this had to be the best taste in the world!

Cas started moaning in his sleep, pushing his ass back against Dean, and finally, Dean flipped him over onto his back, pushed his legs up and filled his unsuspecting hole with his cock while holding onto his ankles. This woke Cas up who was immediately on board, urging Dean on with moans of “Alpha! Yes!”

Even though this turned Dean’s alpha crazy, he forced himself to slow down instead of just fucking another load into his omega. He let go of Cas’ legs and lay down on top of him so that he could suckle on the claiming bite he’d placed on him during his last rut.

He had to get Cas’ mating gland nice and ready for the fake mating bite. Of course, the fact that Cas was in heat meant he already was primed and ready for an alpha to take him— _really_ take him, mate him, breed him, the whole shebang. All the right hormones were rushing through him.

Dean suckled on the mating gland harder as he continued sliding his cock languidly in and out of Cas. When he paused for a moment to look down at Cas and saw a flicker of gold flash in the omega’s eyes, he knew Cas was ready to receive the ‘mating bite.’

There was so much love in Cas’ eyes that Dean wished with all his heart this was for real. Not just them playing around. Not just hormones making Cas look at him like that.

“Dean…” Cas said, reaching up to give _Dean’s_ mating gland an affectionate fondle. A jolt of surprise shot through him and he felt his own mating hormones go crazy with an undefined need.

“Dean, come on,” Cas urged. “Need you to make me yours!”

And that was it. Hearing that same raw need Dean was feeling in Cas’ voice made him growl possessively, “Gonna mate you. Gonna mate you right now!”

“Yes! Yes, please!” Cas begged, baring his neck and showing off the swollen claiming bite glistening with Dean’s saliva.

Dean had forgotten to keep fucking Cas for a moment, but he quickly picked up the pace again as he kissed the omega to show him how loved he was before focusing his attention on the claiming bite once more and nibbling on it, bringing his teeth in on the action.

“Harder!” Cas demanded, tilting his head even further to the side in order to give Dean more room to work with.

“Any harder and I break skin,” Dean replied, frustrated that he couldn’t give his omega what he was asking for.

At least he could give him something else that he needed: his spunk that would alleviate this bout of heat.

When he felt the walls of Cas’ asshole quiver in anticipation, his cock swelled even further, getting ready to deliver the load. He had to slam his eyes shut because Cas’ channel massaging the length of his prick felt too good.

When he opened his eyes again, Cas was staring right at him, biting his lower lip as he met Dean thrust by thrust.

“Alpha! Breed me up!” he said. “Fill my belly with your pups!”

Dean’s hips stuttered and he groaned. How did Cas always know how to get him hot and bothered?

“Touch yourself!” he ordered because there was no way he’d be able to hold back much longer.

Cas hurriedly complied while Dean ducked down and bit at Cas’ mating gland again. That was it. The omega completely lost it as his prick shot off jet after jet—an unusual amount for an omega.

Dean held his hips still as he filled him up spurt by spurt with his own spunk. To make sure nothing went to waste, he shoved his knot past the rim to connect them.

Once his dick had stopped shooting spunk up Cas’ hole, he reached over to the nightstand where they had put out a washcloth and quickly wiped up Cas’ semen before lying down on top of Cas and kissing him again because that had been awesome.

The omega went back to nuzzling Dean’s neck, biting at his mating gland. “Can I mate you?”

Apparently, they were still in the middle of their mating game, and Dean was completely on board. This was the best game ever.

“Yeah, let’s mate,” he said, and then Cas went back to nuzzling, nibbling and biting, harder than before, and Dean playfully bit back.

Later, when they were still lying there knotted together, the smell of content mate made his heart flutter. There was no scent in the world that could ever measure up to—

Wait—mate?

Dean looked down at Cas, who had closed his eyes and was smiling slightly. His eyes were immediately drawn to his neck.

Oh shit! That looked like broken skin right there.


	15. Chapter 15

Dean resisted the urge to burrow into his mate’s warmth and take in the awesome scent that told him Cas was finally _his_. This was not the time to take advantage of something Cas hadn’t even consented to!

Instead, he took a closer look at Cas’ neck—sure enough, that was a mating bite. (Not that there had been any doubt at this point.) While his alpha was preening with pride, Dean was starting to _freak out_.

First things first.

He carefully reached over to the nightstand (which was harder than he thought since his knot hadn’t gone down yet and he kind of had to drag Cas along). Once he had managed to get a hold of his cell phone, he googled for ‘accidental matings.’ More than 13 million results. Although some of the top results seemed to be movie plots. Or porn sites.

He scrolled through some forum posts that were talking about how drunken one-night stands had led to an unwanted mating bond. Then there were the ones raving about how far science has come in regards to breaking mating bonds. There were hormone injections and the like which apparently worked super fast.

It was funny. Before he had met Cas, he hadn’t wanted to engage in heat sex with omegas for fear of being bound to them. He had never thought of what an accidental mating would be like for the _omega_ , he had just been afraid he’d end up stuck with some random omega because of a mistake during sex.

Now that he had mated _Cas_ , though, the only fear he had was that Cas would regret it. Dean, he’d be okay with being bound to Cas forever. All right, that was a lie—he wasn’t ‘okay’ with it, it would be the best fucking thing that had ever happened to him.

But what would Cas say when he—

“Dean?” And here it came. Cas was blinking his eyes open. Any second now, he would realize what Dean had done. “Are you seriously on your phone while we’re _tied_ together?”

“No. Well, yes, but… I’m sorry, I’ll put it away.” He reached over once more, doing just that while trying to come up with a gentle way of breaking the news to Cas. Although he _had_ to have picked up on the scent by now, surely…?

“I was trying to tease you,” Cas clarified. “Did that not come across?” A shy smile appeared on his face then and he added, “You know, I’ve heard that’s what mates do, tease each other?”

“Yeah, about that…” Dean started. Time to come clean and make Cas aware of the fact that it wasn’t a game anymore—even though Dean would have preferred to do that when his knot wasn’t stuck in Cas’ asshole, but what you gonna do? At least the fact that they had just had some satisfying orgasms together meant that neither of them were having crazy urges to keep fucking right now.

Dean took a deep breath and said, “I actually broke some skin.” He touched Cas’ mating bite to turn his attention to what had happened. When Cas just frowned at him, he decided to get even more direct. “I mated you for real. But I actually read up on some ways to break a mating bond and I think—”

“Break a mating bond?” The frown was still on Cas’ face.

“Yeah. Clearly neither of us meant for the… uhm... the game to go that far. But we’re not the first this has happened to and there are ways to… take care of this kind of thing.”

“Oh.” Dean would give anything to get the scent of content mate back because this? This was the scent of sad mate and Dean didn’t care for it one bit. All his instincts were telling him to wrap Cas up in his arms, nuzzle into him and make it all better. It seemed like a strong bond had already started forming between them if Cas’ omega got sad at the thought of breaking it even though he hadn’t even wanted it to begin with.

“I’m sorry,” Cas continued.

“What are _you_ sorry for?” If anyone should be sorry, it was clearly Dean.

“I bit you first.”

Only then did Dean realize that his neck actually did feel a bit sore in the best possible way. He reached up to his own neck and—yep. That felt like a mating bite.

Cas, meanwhile, mumbled, “I thought you… But of course you didn’t.”

“Don’t worry about it,” Dean waved his concerns off. “You were having a bout of heat. You probably would have mated a goat.—Ouch!” he added when Cas punched him in the arm.

“I can’t believe that you still think that’s how heats work.”

He looked so miffed that Dean softly stroked his mating bite on instinct. Using their mating bond to calm his omega down was probably not the smartest thing to do considering that it had been an unplanned mating. But his dick was still lodged safely inside of Cas’ drenched hole and the scent of mate was all around him, so battling his instincts seemed close to impossible.

“Well, you are very… demanding during your heat,” Dean explained. “Y’know, wanting me to mate and breed you. What am I supposed to think?”

“Yes, demanding of _you_ , not of a _goat_.”

Dean rolled his eyes all the while continuing to softly stroke Cas’ mating bite because while Cas had still sounded a bit mad, he was leaning into it, baring his neck for Dean. Dean’s alpha was thrilled at the sight, but Dean tried to keep a level head.

“Will you forget about the goat? That was a joke.” Clearly. “What I meant was, any other alpha.” He hesitated and then added, heart pounding, “Right?”

Hope was a dangerous thing. Some part of him truly hoped that Cas would say, ‘Wrong.’ That he’d say, ‘It’s you and only you.’

But of course he didn’t. Cas’ face shut down and he pressed out, “Right.”

Then he twisted away from Dean, dislodging his dick, making Dean aware of the fact that his knot had gone down. Cum came gushing out of Cas’ hole once it wasn’t plugged up any more, and Cas said, “I should clean this up.”

The next second, he was out of the bed, bunching up the sheets so that Dean had to get up as well.

“You staying for the rest of our cycle?” Cas asked, his voice clipped. “Because I’m pretty sure the next bout of heat that would make me ‘mate a goat’ isn’t that far away.” Somehow, even with the sheets in his arms, he still managed to air-quote.

His scent had turned sour, but Dean had no idea how to make this better without being able to nuzzle against his mating bite and hold him tight, so he just said, “Yeah, sure.”

Having an angry mate on his hands was so not something he knew how to deal with because all his alpha wanted to do was comfort him and hunt down whoever had made his omega miserable, but Cas didn’t seem to want his comfort and Dean didn’t really know _why_ he was miserable. He doubted it was because of one insensitive joke about a goat.

While Cas was putting the sheets into the laundry, Dean was trying to figure out what the problem was. Sure, an accidental mating was probably not what Cas had signed up for, but Dean had told him that there were ways to get the bond dissolved.

When Cas came back with new sheets and started making the bed, Dean still hadn’t come up with anything intelligent to say, so he settled on, “That such a good idea? We’ll probably ruin them too.”

Cas’ dark look told him that he should have just kept his mouth shut. “Comments from alphas are not appreciated right now,” Cas told him before climbing back onto the bed and then… frigging _presenting_ for him.

“Just fuck me,” he said, going down on his elbows and apparently waiting for Dean to mount him.

Dean stayed put and crossed his arms. “I’m not having sex with you when you’re mad at me.”

Throwing a look over his shoulder, Cas said, “Why not? That’s the only reason you’re here, right? So, if you won’t give me your ‘potent alpha seed,’ then maybe I should just call ‘any other alpha.’”

“Okay, that’s it!” Dean joined Cas on the bed, but instead of mounting him, he pulled him into an embrace, making him give up the presenting position and lie down next to Dean instead. “You’re my _mate_! Of course I’ll provide for you and I’ll fill you up again once you need it. But right now, we have to talk about what’s going on here.”

Cas visibly calmed down once Dean started scenting away at his mating bite. His scent still screamed of upset omega, but the mating bond definitely helped keep them both grounded. And maybe that was the reason Cas let go of his anger after burying his face in Dean’s neck and taking a few calming breaths. He even flicked his tongue over Dean’s mating bite a couple times, which made Dean’s alpha all mellow and cuddly.

“I wasn’t,” Cas finally said. “Having a bout of heat when I bit you. You had just taken care of it, I had your seed and your knot and everything was just perfect and… it wasn’t the heat that made me want that.” He bit his lip and looked up at Dean, eyes sorrowful. “I’m sorry that I didn’t realize you were just playing around.”

“I wasn’t playing around,” Dean quickly reassured him, throat dry, hope coursing through him once again. “I mean, I was at first, but I… I thought _you_ were.”

“Well, I wasn’t.”

“Me neither.”

They stared at each other, neither quite comprehending what this meant.

“So… we’re mated?” Dean finally asked, hoping Cas would understand that the _real_ question was, ‘Wanna _stay_ mated?’

A small smile played around Cas’ lips, and the sour scent finally turned hopeful and happy and downright delicious again. “We’re mated,” he agreed.

“Well, hello there, mate.” Dean gave him a flirty smile and then ducked down to give his mate (mate!) a passionate kiss.

He simply couldn’t _wait_ to start their life as a mated couple.


	16. Chapter 16

They used the time they had left before the hormones would overwhelm them again to talk about how things would change for them now that they were mated.

Of course, it was easier to talk about what his _alpha_ needed, so Dean started them off with the most important thing they hadn’t put into words yet, “My alpha needs to feel loved.”

That sounded a bit omega flick-y, but it was the truth and he was just talking about ‘his alpha’ anyway, so it wasn’t like a rejection could hurt him.

“That shouldn’t be a problem seeing how crazy in love my omega is with him,” Cas stated calmly.

Dean realized that he had really needed to hear that, and he couldn’t help but smile brightly at his mate. But he was more attuned than ever with Cas’ scent and so he immediately smelled that the omega wasn’t as blasé about it as he wanted Dean to believe, which gave him the courage to blurt out, “I’m crazy in love with _you_.”

“You are?” Cas asked shyly as if there had been any doubt about it. They were _mated_ for crying out loud.

Still, Dean replied by humming his approval and scenting his mate’s neck just because he could.

“Me too,” Cas mumbled against Dean’s own neck and even though Dean already knew that by now, his heart gave a flutter and Dean felt his alpha stir within him. His rut would soon demand he consummate the mating.

That’s why he continued with another point he had to address while they were still clear-minded, “I want us to move in together.” After all, how was he supposed to ever wake up again without his mate right there next to him? His alpha would go _crazy_ if he didn’t know whether his mate was safe.

“Of course,” Cas agreed. When he looked like he wanted to say something else, Dean raised his eyebrows, inviting him to share what it was he wanted to put out there. Cas began, a bit hesitantly, “I know it’s not really necessary when we’re already mated, but I would like to get married. I mean not right now. Eventually. Maybe. If you…”

“Done,” Dean cut in. “But you have to wait for me to ask. You already proposed the mating.” He was the alpha, dammit! He was supposed to come up with a romantic proposal.

“Well, apparently, I didn’t do it right. You thought I was joking.”

“Not joking. Role-playing,” Dean corrected. “Oh, which reminds me. I know we were role-playing before when you asked me to… ahem… ‘fill your belly with pups.’” Cas actually blushed at that even though he had been the one to say it during the throes of passion. “But I do want pups with you. Do you—”

“Yes,” Cas interrupted him.

“Cool.”

“Then maybe you should put your penis inside of me again,” Cas suggested, ignoring the fact that those words made Dean’s alpha want to pounce him again. “The more seed you put in here during my heat, the better the chances of me catching.”

Lovingly stroking Cas’ belly, trying to imagine it rounded with pups, Dean asked, “Aren’t you on birth control though?”

“So?” Cas raised a challenging eyebrow, and Dean felt his control slip at the sight. If this omega challenged him to breed him right now, he would make sure to pump him full of as much spunk as possible.

His dick twitched with interest—his rut had it already standing at attention. One wrong move from this omega and he’d have an alpha’s cock stuck in his hole quicker than he could tilt his head.

“Your seed is classified at potency level three,” Cas reminded him. “Plus, our cycles are currently synched. If we do have a shot at getting me pregnant even when I’m on birth control, this would be it.”

Challenge accepted.

Since Cas’ hole was still fucked open from taking his knot, Dean slipped right in, his cock feeling snug and at home in his omega. It was tight, but soaked. Someone was obviously about to have another bout of heat if the fast slick production was anything to go by.

About to fuck _his mate_ for the first time, Dean kissed him for all he was worth.

“Your womb better get ready for some potency level three premium alpha spunk,” he grinned down at Cas once his lips were all glistening and swollen from the kisses.

“You’re ridicul—aaaaaaaaah!” Cas moaned and then didn’t say anything anymore, too busy meeting his thrusts when Dean gave in to his alpha and let him out to do what came naturally and fuck some pups into his mate.

⁂

Cas entered the pharmacy once more, this time not in order to buy some alpha spunk (no need for that anymore, now that he had mated the best alpha out there), but hand-in-hand with said alpha. Just holding hands was enough to make his omega all giddy.

Dean was the sweetest alpha, and now that they were mated, he liked making sure that everyone knew that by scent-marking him, biting at his mating bite until it was all red again, or just simply holding hands or walking arm in arm.

He stopped short when he saw who Sam was talking to.

“Gabe?” Cas asked.

“Oh. Hey, bro.”

They greeted Sam as well and then Cas turned back to Gabe. “What are you doing here?”

“Getting to know my bro-in-law. What are _you_ doing here? His swimmers not doing the job anymore?” He nodded towards Dean, a glint in his eyes that clearly meant he was trying to mess with Dean.

And succeeded in doing so. Dean shot him a dark look. “Hey! I resent that! I’m sure my seed does a better job than yours ever could.”

“Ew, that’s gross, that’s his _brother_!” Sam chimed in.

“What? I didn’t mean like _that_. Just… in general.”

Cas rolled his eyes. Holidays would sure be fun now that they were all one pack.

“So, what _are_ you doing here?” Sam asked, and Cas remembered to slip over the prescription.

Sam looked down at it, then his eyes widened and he looked up, his nose twitching ever so slightly as he scented in Cas’ direction.

“Dude, stop trying to scent my mate!” Dean said, taking a protective step towards Cas.

Gabe, meanwhile, was leaning forward to get a glimpse at the prescription as well, and then shouted, “Congrats!” and pulled Cas into a hug before turning to Dean. “Seems like your swimmers do get the job done.”

Sam had come around the counter as well to get some hugs in.

“Wow, I’m so happy for you!”

They all smiled at each other until Dean finally said, “So, are we getting those prenatal vitamins or what?”

While Sam went to search for the vitamins and Gabe took a look at the shelf with omega slick, Dean turned to Cas.

“So. Wanna go home after this and test if my seed is as potent as advertised?” He did a strange thing with his eyebrows, probably trying to convey some secret meaning.

But try as he might, Cas could not figure out what that meaning was, so he asked, “Why would we need to test that? I am already with pup.” Maybe Dean needed reassurance after Gabe had made that dig at him earlier, so he added, “Clearly, you are a very manly alpha whose seed can get your mate pregnant without problems.”

Rolling his eyes, Dean said, “Cas, we’ve talked about this. It’s flirting? It’s a way for me to see if you’re receptive to my advances?”

“Oh. In that case: yes, I would like to have intercourse with you.”

Sam had to have swallowed the wrong way because he started choking a few feet away, and Gabe had to have found something funny on that shelf because he started laughing—but all of that didn’t matter. What mattered was that Dean, his mate, was still so sweet and caring, still trying to flirt with him to gauge if he was interested in starting something.

Cas could make an effort to flirt back once in a while. So, he took Dean’s hand again and kissed it, showing his alpha that he was receptive alright. After all, he would always be receptive where Dean was concerned.

**Author's Note:**

> Someone expressed interest in a sequel, so look out for a potential sequel (maybe, not sure). Or a companion piece. I’m thinking along the lines of ‘Omega Slick.’ In the meantime, I'll post the next chapter of "The Alpha Next Door" during the next couple of days, so I hope you have fun with that.
> 
> Thank you to everyone who commented on this fic. Without you, I probably wouldn't have been able to finish it. ❤️ ❤️ ❤️
> 
> And if you want to support me another way, reblogging the link on tumblr would be awesome. **[Here's the link to the tumblr post](https://destielshipper4cas.tumblr.com/post/611775355249983488/alpha-spunk-finished-rating-explicit-tags)**.
> 
>  **Update** : I started working on the companion piece.
> 
>  _Title_ : "Omega Slick."  
>  _Summary:_ When Dean’s ruts become unbearable, he decides to buy omega slick in order to get them under control. When he returns to the sex store for more, he meets the omega whose slick he’s been using, and can’t help but fall for him hard and fast.


End file.
